TEI P4 Guidelines for Electronic Text Encoding and Interchangeprojects.oucs.ox.ac.uk/teiweb/P4X/driver.pdf · 1.1 Structure and Notational Conventions of this Document 4 1.1.1 Structure

The TEI Consortium

The Association for Computers and the Humanities (ACH);The Association for Computational Linguistics (ACL);

The Association for Literary and Linguistic Computing (ALLC)

TEI P4Guidelines for Electronic Text

Encoding and InterchangeXML-compatible edition

edited by C M Sperberg-McQueenand Lou Burnard

XML conversion by Syd Bauman, Lou Burnard,Steven DeRose, and Sebastian Rahtz

Oxford — Providence — Charlottesville — BergenJune 2004

Guidelines for Electronic Text Encoding and Interchange

© 1990, 1992, 1993, 1994 ACH, ACL, ALLC.© 2002 TEI Consortium

Published for the TEI Consortium by the Humanities Computing Unit, University of Oxford

ISBN 0-952-33013-X

ContentsI Introduction 1

1 About These Guidelines 31.1 Structure and Notational Conventions of this Document 4

1.1.1 Structure 41.1.2 Notational Conventions 5

1.2 Underlying Principles and Intended Use 61.2.1 Design Principles of the TEI Scheme 71.2.2 Intended Use 8

1.2.2.1 Use in Text Capture and Text Creation 81.2.2.2 Use for Interchange 91.2.2.3 Use for Local Processing 10

1.3 Historical Background 111.3.1 Origin and Development of the TEI 111.3.2 Future Developments 12

2 A Gentle Introduction to XML 132.1 What’s special about XML? 14

2.1.1 Descriptive markup 142.1.2 Types of document 142.1.3 Data independence 15

2.2 Textual structure 152.3 XML structures 16

2.3.1 Elements 162.3.2 Content models: an example 16

2.4 Validating a document’s structure 182.4.1 An example DTD 182.4.2 Generic identifier 182.4.3 Content model 192.4.4 Occurrence indicators 192.4.5 Connectors 192.4.6 Model groups 19

2.5 Complicating the issue 212.6 Attributes 22

2.6.1 Declaring attributes 222.6.2 Attribute names 232.6.3 Attribute values 232.6.4 Default value 232.6.5 ID and IDREF attributes 24

2.7 Entities 252.7.1 Entity declarations 252.7.2 Entity references 262.7.3 Character references 262.7.4 Unparsed entities and Notations 272.7.5 Parameter entities 27

2.8 Marked sections 282.8.1 CDATA marked section 282.8.2 Conditional marked section 29

2.9 Other components of an XML document 302.9.1 Processing instructions 302.9.2 Namespaces 31

2.10 Putting it all together 322.10.1 SGML and XML declarations 322.10.2 The DOCTYPE declaration 322.10.3 The Document Instance 34

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2.10.4 Ancillary Files 343 Structure of the TEI Document Type Definition 35

3.1 Main and Auxiliary DTDs 353.2 Core, Base, and Additional Tag Sets 36

3.2.1 The Core Tag Sets 373.2.2 The Base Tag Sets 373.2.3 The Additional Tag Sets 383.2.4 User-Defined Tag Sets 39

3.3 Invocation of the TEI DTD 393.4 Combining TEI Base Tag Sets 403.5 Global Attributes 423.6 The TEI2.DTD File 45

3.6.1 Structure of the TEI2.DTD File 453.6.2 Embedding Local Modifications 473.6.3 Embedding the Core Tag Sets 483.6.4 Embedding the Base Tag Set 483.6.5 Embedding the Additional Tag Sets 49

3.7 Element Classes 503.7.1 Classes Which Share Attributes 503.7.2 Classes Used in Content Models 523.7.3 The TEICLAS2.ENT File 533.7.4 Low-Level Element Classes 543.7.5 High-Level Element Classes 563.7.6 Elements Marked for Text Type 573.7.7 Standard Content Models 583.7.8 Components in Mixed and General Bases 593.7.9 Miscellaneous Content-Model Classes 60

3.8 Other Parameter Entities in TEI DTDs 613.8.1 Inclusion and Exclusion of Elements 623.8.2 Parameter Entities for Element Generic Identifiers 623.8.3 Parameter Entities for TEI Keywords 623.8.4 Generation of an XML DTD 633.8.5 Declaration of TEI keywords 63

II Core Tags and General Rules 654 Languages and Character Sets 67

4.1 A simple character encoding model 674.1.1 Some definitions 684.1.2 Characters and glyphs 694.1.3 Characters and their encoding 704.1.4 Character semantics 724.1.5 Characters from the Private Usage Area 72

4.2 Entry and display of characters 734.2.1 Character input and entity references 734.2.2 Transliteration schemes 75

4.3 Code shifting 754.4 The Writing System Declaration 77

5 The TEI Header 795.1 Organization of the TEI Header 79

5.1.1 The TEI Header and Its Components 805.1.2 Types of Content in the TEI Header 81

5.2 The File Description 825.2.1 The Title Statement 835.2.2 The Edition Statement 855.2.3 Type and Extent of File 87

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5.2.4 Publication, Distribution, etc. 885.2.5 The Series Statement 895.2.6 The Notes Statement 915.2.7 The Source Description 925.2.8 Computer Files Derived from Other Computer Files 945.2.9 Computer Files Composed of Transcribed Speech 94

5.3 The Encoding Description 965.3.1 The Project Description 975.3.2 The Sampling Declaration 985.3.3 The Editorial Practices Declaration 995.3.4 The Tagging Declaration 1025.3.5 The Reference System Declaration 103

5.3.5.1 Prose Method 1055.3.5.2 Stepwise Method 1055.3.5.3 Milestone Method 106

5.3.6 The Classification Declaration 1085.3.7 The Feature System Declaration 1095.3.8 The Metrical Declaration Element 1105.3.9 The Variant-Encoding Method Element 112

5.4 The Profile Description 1125.4.1 Creation 1135.4.2 Language Usage 1135.4.3 The Text Classification 114

5.5 The Revision Description 1165.6 Minimal and Recommended Headers 1185.7 Note for Library Cataloguers 121

6 Elements Available in All TEI Documents 1236.1 Paragraphs 1246.2 Treatment of Punctuation 1256.3 Highlighting and Quotation 126

6.3.1 What Is Highlighting? 1276.3.2 Emphasis, Foreign Words, and Unusual Language 128

6.3.2.1 Foreign Words or Expressions 1286.3.2.2 Emphatic Words and Phrases 1296.3.2.3 Other Linguistically Distinct Material 130

6.3.3 Quotation 1306.3.4 Terms, Glosses, and Cited Words 1346.3.5 Some Further Examples 135

6.4 Names, Numbers, Dates, Abbreviations, and Addresses 1366.4.1 Referring Strings 1366.4.2 Addresses 1386.4.3 Numbers and Measures 1396.4.4 Dates and Times 1416.4.5 Abbreviations and Their Expansions 143

6.5 Simple Editorial Changes 1446.5.1 Correction of Apparent Errors 1456.5.2 Regularization and Normalization 1476.5.3 Additions, Deletions, and Omissions 148

6.6 Simple Links and Cross References 1526.7 Lists 1546.8 Notes, Annotation, and Indexing 157

6.8.1 Notes and Simple Annotation 1576.8.2 Index Entries 159

6.9 Reference Systems 160

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6.9.1 Using the ID and N Attributes 1616.9.2 Creating New Reference Systems 1626.9.3 Milestone Tags 1636.9.4 Declaring Reference Systems 166

6.10 Bibliographic Citations and References 1676.10.1 Elements of Bibliographic References 1686.10.2 Components of Bibliographic References 171

6.10.2.1 Analytic, Monographic, and Series Levels 1716.10.2.2 Authors, Titles, and Editors 1736.10.2.3 Imprint, Pagination, and Other Details 1766.10.2.4 Series Information 1796.10.2.5 Notes and Other Additional Information 1796.10.2.6 Order of Components within References 180

6.10.3 Bibliographic Pointers 1806.10.4 Relationship to Other Bibliographic Schemes 181

6.11 Passages of Verse or Drama 1826.11.1 Core Tags for Verse 1826.11.2 Core Tags for Drama 184

6.12 Overview of the Core Tag Set 1877 Default Text Structure 189

7.1 Divisions of the Body 1907.1.1 Un-numbered Divisions 1917.1.2 Numbered Divisions 1917.1.3 Numbered or Un-numbered? 1937.1.4 Partial and Composite Divisions 195

7.2 Elements Common to All Divisions 1967.2.1 Headings and Trailers 1967.2.2 Openers and Closers 1977.2.3 Arguments and Epigraphs 1997.2.4 Content of Textual Divisions 200

7.3 Groups of Texts 2017.4 Front Matter 2067.5 Title Pages 2087.6 Back Matter 2107.7 DTD Fragment for Default Text Structure 212

III Base Tag Sets 2138 Base Tag Set for Prose 2159 Base Tag Set for Verse 217

9.1 Structure of the Base Tag Set for Verse 2179.2 Structural Divisions of Verse Texts 2189.3 Components of the Verse Line 2219.4 Rhyme and Metrical Analysis 224

9.4.1 Sample Metrical Analyses 2249.4.2 Segment-Level versus Line-level Tagging 2269.4.3 Metrical Analysis of Stanzaic Verse 226

9.5 Rhyme 2279.6 Encoding Procedures For Other Verse Features 228

10 Base Tag Set for Drama 23110.1 Front and Back Matter 232

10.1.1 The Set Element 23210.1.2 Prologues and Epilogues 23310.1.3 Records of Performances 23510.1.4 Cast Lists 236

10.2 The Body of a Performance Text 239

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10.2.1 Major Structural Divisions 23910.2.2 Speeches and Speakers 24010.2.3 Stage Directions 24210.2.4 Speech Contents 24410.2.5 Embedded Structures 24610.2.6 Simultaneous Action 249

10.3 Other Types of Performance Text 24910.3.1 Technical Information 251

11 Transcriptions of Speech 25311.1 General Considerations and Overview 254

11.1.1 Divisions 25511.2 Elements Unique to Spoken Texts 256

11.2.1 Utterances 25911.2.2 Pause 26011.2.3 Vocal, Kinesic, Event 26011.2.4 Writing 26211.2.5 Temporal Information 26211.2.6 Shifts 26211.2.7 Formal Definition 265

11.3 Elements Defined Elsewhere 26511.3.1 Segmentation 26611.3.2 Synchronization and Overlap 26711.3.3 Regularization of Word Forms 27111.3.4 Prosody 27111.3.5 Speech Management 27211.3.6 Analytic Coding 273

12 Print Dictionaries 27512.1 Dictionary Body and Overall Structure 27612.2 The Structure of Dictionary Entries 278

12.2.1 Hierarchical Levels 27912.2.2 Groups and Constituents 280

12.3 Top-level Constituents of Entries 28512.3.1 Information on Written and Spoken Forms 28512.3.2 Grammatical Information 29012.3.3 Sense Information 292

12.3.3.1 Definitions 29212.3.3.2 Translation Equivalents 293

12.3.4 Etymological Information 29512.3.5 Other Information 297

12.3.5.1 Examples 29712.3.5.2 Usage Information and Other Labels 29812.3.5.3 Cross References to Other Entries 30112.3.5.4 Notes within Entries 303

12.3.6 Related Entries 30412.4 Headword and Pronunciation References 30512.5 Typographic and Lexical Information in Dictionary Data 308

12.5.1 Editorial View 30912.5.2 Lexical View 31112.5.3 Retaining Both Views 312

12.5.3.1 Using Attribute Values to Capture Alternate Views 31212.5.3.2 Recording Original Locations of Transposed Elements 314

12.5.4 Attributes for Dictionary Elements 31512.6 Unstructured Entries 315

13 Terminological Databases 317

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13.1 The Terminological Entry 31713.2 Tags for Terminological Data 31813.3 Basic Structure of the Terminological Entry 323

13.3.1 Nested Term Entries 32313.3.2 Flat Term Entries Using Rules of Adjacency 32313.3.3 Flat Term Entries Using Group and Depend Attributes 32413.3.4 References between Term Entries 326

13.4 Overall Structure of Terminological Documents 32613.4.1 DTD Fragment for Nested Style 32813.4.2 DTD Fragment for Flat Style 329

13.5 Additional Examples of Term Entries 32913.5.1 Example Term Entry from ISO 472 33013.5.2 The Example Treated as a Single Term Entry in Nested Form 33013.5.3 The Example Treated as Two Separate Term Entries in Nested Form 33113.5.4 The Example Treated as a Flat Term Entry Using Adjacency Rules 33213.5.5 The Example Treated as a Flat Term Entry Not Using Adjacency Rules 332

IV Additional Tag Sets 33514 Linking, Segmentation, and Alignment 337

14.1 Pointers 33814.1.1 Pointers and Links 33914.1.2 Using Pointers and Links 34014.1.3 Groups of Links 34314.1.4 Intermediate Pointers 346

14.2 Extended Pointers 34614.2.1 Extended Pointer Elements 34714.2.2 Extended Pointer Syntax 347

14.2.2.1 Location Ladders 34814.2.2.2 Location Terms 34814.2.2.3 The ROOT Keyword 34914.2.2.4 The HERE Keyword 35014.2.2.5 The ID Keyword 35014.2.2.6 The REF Keyword 35014.2.2.7 The CHILD Keyword 35014.2.2.8 The DESCENDANT Keyword 35314.2.2.9 The ANCESTOR Keyword 35314.2.2.10 The PREVIOUS Keyword 35414.2.2.11 The NEXT Keyword 35414.2.2.12 The PRECEDING Keyword 35414.2.2.13 The FOLLOWING Keyword 35514.2.2.14 The PATTERN Keyword 35514.2.2.15 The TOKEN Keyword 35614.2.2.16 The STR Keyword 35714.2.2.17 The SPACE Keyword 35714.2.2.18 The FOREIGN Keyword 35814.2.2.19 The HYQ Keyword 35814.2.2.20 The DITTO Keyword 358

14.2.3 Using Extended Pointers 35914.2.4 Representation of HTML links in TEI 360

14.3 Blocks, Segments and Anchors 36214.4 Correspondence and Alignment 366

14.4.1 Correspondence 36714.4.2 Alignment of Parallel Texts 36814.4.3 A Three-way Alignment 370

14.5 Synchronization 372

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14.5.1 Aligning Synchronous Events 37314.5.2 Placing Synchronous Events in Time 374

14.6 Identical Elements and Virtual Copies 37614.7 Aggregation 37714.8 Alternation 38114.9 Connecting Analytic and Textual Markup 386

15 Simple Analytic Mechanisms 38715.1 Linguistic Segment Categories 38815.2 Global Attributes for Simple Analyses 39215.3 Spans and Interpretations 39215.4 Linguistic Annotation 396

16 Feature Structures 40116.1 Introduction 40116.2 Elementary Feature Structures: Features with Binary Values 40216.3 Feature, Feature-Structure and Feature-Value Libraries 40416.4 Symbolic, Numeric, Measurement, Rate and String Values 40616.5 Structured Values 41216.6 Singleton, Set, Bag and List Collections of Values 41316.7 Alternative Features and Feature Values 41616.8 Boolean, Default and Uncertain Values 42016.9 Indirect Specification of Values Using the rel Attribute 423

16.9.1 The Not-Equals Relation 42316.9.2 Other Inequality Relations 42416.9.3 Subsumption and Non-subsumption Relations 42516.9.4 Relations Holding with Sets, Bags, and Lists 42716.9.5 Varieties of Subsumption and Non-subsumption 428

16.10 Two Illustrations 42917 Certainty and Responsibility 435

17.1 Levels of Certainty 43517.1.1 Using Notes to Record Uncertainty 43617.1.2 Structured Indications of Uncertainty 436

17.2 Attribution of Responsibility 43918 Transcription of Primary Sources 441

18.1 Altered, Corrected, and Erroneous Texts 44218.1.1 Use of Core Tags for Transcriptional Work 44218.1.2 Abbreviation and Expansion 44518.1.3 Correction and Conjecture 44718.1.4 Additions and Deletions 44818.1.5 Substitutions 45218.1.6 Cancellation of Deletions and Other Markings 45418.1.7 Text Omitted from or Supplied in the Transcription 455

18.2 Non-Linguistic Phenomena in the Source 45618.2.1 Document Hands 45718.2.2 Hand, Responsibility, and Certainty Attributes 45918.2.3 Damage, Illegibility, and Supplied Text 46018.2.4 Use of the Gap, Del, Damage, Unclear and Supplied Tags in Combination 46318.2.5 Space 46418.2.6 Lines 464

18.3 Headers, Footers, and Similar Matter 46518.4 Other Primary Source Features not Covered in These Guidelines 466

19 Critical Apparatus 46719.1 The Apparatus Entry, Readings, and Witnesses 468

19.1.1 The Apparatus Entry 46819.1.2 Readings 469

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19.1.3 Indicating Subvariation in Apparatus Entries 47219.1.4 Witness Information 474

19.1.4.1 Witness Detail Information 47419.1.4.2 Witness Information in the Source 47519.1.4.3 The Witness List 476

19.1.5 Fragmentary Witnesses 47819.2 Linking the Apparatus to the Text 478

19.2.1 The Location-referenced Method 47919.2.2 The Double End-Point Attachment Method 48019.2.3 The Parallel Segmentation Method 482

19.3 Using Apparatus Elements in Transcriptions 48320 Names and Dates 485

20.1 Personal Names 48620.2 Place Names 490

20.2.1 Geo-political Place Names 49220.2.2 Geographic Names 49220.2.3 Relative Place Names 493

20.3 Organization names 49420.4 Dates and Time 497

20.4.1 Absolute Dates and Times 49820.4.2 Relative Dates and Times 500

21 Graphs, Networks, and Trees 50321.1 Graphs and Digraphs 504

21.1.1 Transition Networks 50821.1.2 Family Trees 50921.1.3 Historical Interpretation 510

21.2 Trees 51221.3 Another Tree Notation 515

22 Tables, Formulae, and Graphics 52122.1 Tables 522

22.1.1 The TEI Table DTD 52222.1.2 Other Table DTDs 525

22.2 Formulae and Mathematical Expressions 52622.3 Specific Elements for Graphic Images 52922.4 Overview of Basic Graphics Concepts 53222.5 Graphic Image Formats 533

22.5.1 Vector Graphic Formats 53422.5.2 Raster Graphic Formats 53422.5.3 Photographic and Motion Video Formats 535

23 Language Corpora 53723.1 Varieties of Composite Text 53823.2 Contextual Information 540

23.2.1 The Text Description 54123.2.2 The Participants Description 54523.2.3 The Setting Description 549

23.3 Associating Contextual Information with a Text 55123.3.1 Combining Corpus and Text Headers 55123.3.2 Declarable Elements 55223.3.3 Summary 555

23.4 Linguistic Annotation of Corpora 55523.4.1 Levels of Analysis 556

23.5 Recommendations for the Encoding of Large Corpora 556V Auxiliary Document Types 557

24 The Independent Header 559

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24.1 Definition and Principles for Encoders 55924.2 Required and Recommended Tags 56024.3 Header Elements and their Relationship to the MARC Record 56424.4 MARC Fields for the File Description 56424.5 MARC Fields for the Encoding Description 56624.6 MARC Fields for the Profile Description 56724.7 MARC fields for the Revision Description 56724.8 Structure of the DTD for Independent Headers 568

25 Writing System Declaration 57125.1 Overall Structure of Writing System Declaration 57125.2 Identifying the Language 57325.3 Describing the Writing System 57425.4 Documenting the Character Set and Its Encoding 575

25.4.1 Base Components of the WSD 57525.4.2 Exceptions in the WSD 57725.4.3 Documenting Coded Character Sets and Entity Sets 58125.4.4 Documenting Transliteration Schemes 581

25.5 Notes in the WSD 58125.6 Linkage between WSD and Main Document 58125.7 Predefined TEI WSDs 58225.8 Details of WSD Semantics 582

25.8.1 WSD Semantics: General Principles 58325.8.2 Semantics of WSD Base Components 58325.8.3 Multiple Base Components 58425.8.4 Semantics of Exceptions 584

25.8.4.1 Case 1: replacement 58525.8.4.2 Case 2: merger 58525.8.4.3 Case 3: expansion 587

25.8.5 Merger of Form and Character Elements 58726 Feature System Declaration 589

26.1 Linking a TEI Text to Feature System Declarations 58926.2 The Overall Structure of a Feature System Declaration 59126.3 Feature Declarations 59326.4 Feature Structure Constraints 59626.5 A Complete Example 598

27 Tag Set Documentation 60127.1 The TagDoc Documentation Element 603

27.1.1 The AttList Documentation Element 60527.2 Element Classes 60727.3 Entity Documentation 608

VI Technical Topics 61128 Conformance 613

28.1 Definitions of Terms 61328.1.1 TEI-Conformant Document 61328.1.2 TEI Local Processing Format 61328.1.3 TEI Interchange Format 61428.1.4 TEI Packed Interchange format 61428.1.5 TEI Recommended Practice 61428.1.6 TEI Abstract Model 615

28.2 Modifications to TEI SGML Declaration 61528.3 Modifications to TEI Document Type Declarations 61528.4 TEI Processing Model 616

28.4.1 Document Capture and Reclamation 61628.4.2 Local Storage Format and Application Software 617

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28.4.3 Enrichment and Other Processing 61728.4.4 Data Export 61728.4.5 Data Import 61728.4.6 TEI Conformance in the Processing Model 618

28.5 Aspects of Conformance and Document Description 61828.5.1 Character Sets 61828.5.2 SGML Declaration 61928.5.3 Document Type Declaration 61928.5.4 Tag Usage and Feature Marking 61928.5.5 Non-SGML, non-XML Markup 620

29 Modifying and Customizing the TEI DTD 62129.1 Kinds of Modification 623

29.1.1 Suppressing Elements 62329.1.2 Renaming Elements 62429.1.3 Class Extension 62529.1.4 New content models 626

29.2 Documenting the Modifications 62629.3 TEI Lite: an example Customization 627

30 Rules for Interchange 63130.1 Negotiated Interchange 63130.2 Some Simple Examples 63230.3 Non-Negotiated Interchange 63330.4 Notes for Implementors 633

31 Multiple Hierarchies 63531.1 Concurrent Markup of Multiple Hierarchies 63631.2 Boundary Marking with Milestone Elements 63631.3 Fragmentation of Elements 63731.4 Reconstitution of Virtual Elements 63831.5 Multiple Encodings of the Same Information 63831.6 Concurrent Markup for Pages and Lines 639

32 Algorithm for Recognizing Canonical References 643VII Alphabetical Reference Lists of Classes, Entities, and Elements 647

33 Element Classes 64934 Entities 68535 Elements 703

VIII Reference Material 98736 Obtaining the TEI DTD 98937 Obtaining TEI WSDs 99338 Sample Tag Set Documentation 995

38.1 Tag Documentation for the TEI p Element 99538.2 Tag Documentation for the TEI head Element 99538.3 Tag Documentation for the TEI div Element 99638.4 Class Documentation for the TEI Divn Class 997

39 Formal Grammar for the TEI-Interchange-Format Subset of SGML 99939.1 Notation 99939.2 Grammar for SGML Document (Overview) 99939.3 Grammar for SGML Declaration 100039.4 Grammar for DTD 100239.5 Grammar for Document Instance 100439.6 Common Syntactic Constructs 100639.7 Lexical Scanner 100739.8 Differences from ISO 8879 1009

Appendix A Bibliography 1011Appendix B Index 1017

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Appendix C Prefatory Notes 1019Appendix C1. Introductory Note (November 2001) 1019Appendix C2. Introductory Note (June 2001) 1019Appendix C3. Introductory Note (May 1999) 1021

Appendix C3.1. Typographic corrections made 1021Appendix C3.2. Specific changes in the DTD 1021Appendix C3.3. Outstanding errors 1022

Appendix C4. Preface (April 1994) 1023Appendix C5. Acknowledgments 1024

Appendix C5.1. TEI Working Committees (1990-1993) 1024Appendix C5.2. Advisory Board 1026Appendix C5.3. Steering Committee Membership 1026

Appendix D Colophon 1027

Revision History: June 2004

© Text Encoding Initiative Consortium

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In memoriamDonald E. Walker

22 November 1928 – 26 November 1993

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Introductory Note (March 2002) Introductory Note (March 2002)The primary goal of this revision has been to make available a new and corrected version of the TEIGuidelines which:

• is expressed in XML and conforms to a TEI-conformant XML DTD;• generates a set of DTD fragments that can be combined together to form either SGML or

XML document type definitions;• corrects blatant errors, typographical mishaps, and other egregious editorial oversights;• can be processed and maintained using readily available XML tools instead of the

special-purpose ad hoc software originally used for TEI P3.

A second major design goal of this revision has been to ensure that the DTD fragments generated wouldnot break existing documents: in other words, that any document conforming to the original TEI P3SGML DTD would also conform to the new XML version of it. Although full backwards compatibilitycannot be guaranteed, we believe our implementation is consistent with that goal.

In most respects, the TEI Guidelines have stood the test of time remarkably well. The present editionmakes no substantial attempt to rewrite those few parts of them which have now been rendered obsoleteby changes since their first publication, though an indication is given in the text of where such rewritingis now considered necessary. Neither does the present version attempt to address any of the manypossible new areas of digital activity in which the TEI approach to standardization may have somethingto offer. Both these tasks require the existence of an informed and active TEI Council to direct andvalidate such extension and maintenance work, in response to the changing needs and priorities of theTEI user community.

Two exceptions to the above principles may be cited: firstly, the chapter which originally provided a‘Gentle Introduction’ to SGML has been completely rewritten to provide a similarly gentle introductionto XML; secondly the chapter on character sets has been completely revised in light of the closeconnexion between Unicode and XML. The editors gratefully acknowledge the assistance of the ad hocworkgroup chaired by Christian Wittern, which undertook to provide expert advice and correction atvery short notice, in the latter task.

The preparation of this new version relied extensively on preliminary work carried out by the formerNorth American editor of the TEI Guidelines, C.M. Sperberg-McQueen. In a TEI working paper writtenin 19991 he sketched out a precise blueprint for the conversion of the TEI from SGML to XML, whichwe have implemented, with only slight modification.

The Editors would also like to express thanks to the team of volunteers from the TEI community whohelped us with the task of proof reading the first draft during the summer of 2001; and to SebastianRahtz of Oxford University Computing Services, without whose skill and enthusiasm this new editionwould not have been possible.

A substantial proportion of the work of preparing this new edition was funded with the assistance of agrant from the US National Endowment for the Humanities, whose continued support of the TEI hasalso been crucial to the effort of setting up the TEI Consortium.

Finally, we would like to thank all our colleagues on the interim management board of the TEIConsortium, in particular its Chairman John Unsworth, for their continued support of the TEI’s work,and their willingness to devote effort to the difficult task of overseeing its transition to a neworganizational infrastructure.

Summary details of the changes made in the present and previous editions are given in their PrefatoryNotes, all of which are now reproduced in an Appendix to the present edition: see Appendix C PrefatoryNotes.

Lou Burnard and Syd Bauman (TEI Editors) Oxford and Providence, March 2002.

1 TEI ED W69, available from the TEI website at http://www.tei-c.org/Vault/ED/edw69.htm.

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http://www.tei-c.org/Vault/ED/edw69.htm

I: Introduction

June 2004 1 TEI Consortium

1 About These Guidelines 1 About These GuidelinesThese Guidelines have been developed by the Text Encoding Initiative (TEI); see 1.3 Historical Back-ground. They are addressed to anyone who works with any text in electronic form.

They provide means of representing those features of a text which need to be identified explicitly in orderto facilitate processing of the text by computer programs. In particular, they specify a set of markers(or tags) which may be inserted in the electronic representation of the text, in order to mark the textstructure and other textual features of interest. Without such explicit markers, many important featuresremain difficult to locate by mechanical means such as computer programs, and thus difficult to processeffectively. The process of inserting such explicit markers for implicit textual features is often called‘markup’, ‘encoding’, or ‘tagging’, and the term encoding scheme or markup language denotes the ruleswhich govern the use of markup in a set of encodings.

The Guidelines formulated in this document are intended for use in interchange between individualsand research groups using different programs and computer systems over a broad range of applications.Since they contain an inventory of the features most often found useful for text processing, the Guidelinesalso provide help to those creating texts in electronic form. They can also be used for the local storage oftext which is to be processed with multiple software packages requiring different input formats.

The Guidelines apply to texts in any natural language, of any date, in any literary genre or text type,without restriction on form or content. They treat both continuous materials (‘running text’) anddiscontinuous materials such as dictionaries and linguistic corpora. Though principally directed tothe needs of the scholarly research community, the Guidelines are not restricted to esoteric academicapplications. They should also be useful for librarians who maintain and document electronic materials,as well as for publishers and others creating or distributing electronic texts. Although they focuson problems of representing in electronic form texts which already exist in traditional media, theseGuidelines should also be useful for the creation of electronic texts. They are adequate to, but not limitedby, existing practices.

The rules and recommendations made in the these Guidelines are designed to enable the creation ofdocuments that conform to either the Standard Generalized Markup Language (SGML, defined by ISO8879) or the Extensible Markup Language (XML, defined by the World Wide Web Consortium’s XMLRecommendation). XML is a subset of SGML, and the modifications to these Guidelines to supportXML are designed to maximize compatibility with both specifications. For more information on markuplanguages see chapter 2 A Gentle Introduction to XML .

These Guidelines also make reference to character encoding standards such as ISO 646, ISO 10646 andUnicode. ISO 646 defines a standard seven-bit character set in terms of which recommendations oncharacter-level interchange are formulated; this is the most portable character set for broad interchange,but requires indirect encoding of many characters. Unicode provides a much larger character setappropriate for international use, and all XML implementations must support it; however, it is not asof this writing so widely portable as ISO 646.

This document provides the authoritative statement of the requirements and usage of the TEI encodingscheme. Although it includes numerous small examples, it must be stressed that it is intended as areference manual and that readers unfamiliar with SGML, XML, or text markup in general will find itdifficult to learn the encoding scheme by reading this document alone.

This document will be complemented by a series of tutorials in text encoding (document TEI U1 etseq.) and a case book of extended examples with discussion of the rationale for various markup choices(TEI T1).2 Readers seeking an introduction to text markup and the use of the TEI encoding scheme in aspecific area should consult an appropriate tutorial; those already familiar with the scheme and interestedin seeing examples of its application should consult the case book.

The remainder of this chapter comprises three sections. The first gives an overview of the structureand notational conventions used throughout the document. The second enumerates the design principles

2 TEI documents bear identifying numbers which indicate the provenance of the document (here simply “TEI”, in other cases theTEI work group number, e.g. “TEI AI5”), the type of document (here “U” and “T”, meaning users’ guide or users’ manual andsample text(s)), and a sequential number. The TEI document number of the document in hand is TEI P4 (for TEI public proposalnumber 4).


1 About These Guidelines

underlying the TEI scheme and the application environments in which it may be found useful. Finally,the third section gives a brief account of the origins and development of the Text Encoding Initiativeitself.

1.1 Structure and Notational Conventions of this Document 1.1 Structure and NotationalConventions of this Document

1.1.1 Structure 1.1.1 StructurePart I provides some relevant background information about the Guidelines themselves (in this chapter);a brief technical review of markup languages (chapter 2 A Gentle Introduction to XML); and a descriptionof how the TEI document type definition (DTD) is organized (chapter 3 Structure of the TEI DocumentType Definition).

Part II provides a systematic treatment of issues common to all text types: character representation(chapter 4 Languages and Character Sets); in-file documentation of the text (chapter 5 The TEI Header);tags for text features found in all sorts of text: lists, notes, emphasis, quotations, cross-references,technical terms, names, dates, numbers, etc. (chapter 6 Elements Available in All TEI Documents); and adefinition for the default structure of all TEI documents (chapter 7 Default Text Structure).

Part III documents various base tag sets: these include specialized tags for prose, for verse, for dramaand other performance materials, for spoken materials, as well as for letters and memoranda, printeddictionaries, and terminological data. Additional sections discuss user-defined and mixed base tag sets.An instance of the TEI DTD must use one and only one base tag set, unless one of the ‘mixed’ bases isused.

Part IV documents various additional tag sets, which may be included or excluded, as appropriate.Topics covered include a variety of approaches to the analysis and interpretation of texts, and includerepresentations for hypertextual links and other non-hierarchic structures, as well as specialized tags forthe encoding of critical editions and language corpora.

Part V defines certain specialized auxiliary document types, used to encode information about the waythat texts have been encoded, specifically: the TEI header regarded as a distinct document; the TEIWriting System Declaration; the Feature System declaration; and the Tag Set Documentation.

Part VI contains a number of technical discussions of a more specialist interest. Topics covered includethe notion of formal conformance to the TEI Guidelines; the controlled user-modification of the TEIDTD; practical aspects of the use of TEI markup both in local processing and in interchange; and therelationship of TEI markup to other markup standards.

Part VII consists of an alphabetical reference list of all elements and element classes defined in the TEIencoding scheme.

Part VIII provides further reference material: specifically, a description of how to obtain current versionsof the full TEI DTDs and the set of standard Writing System Declarations, a sample Feature SystemDeclaration for basic grammatical annotation, sample tag documentation, and a formal grammar for thesubset of SGML used in the TEI interchange format. No formal subset has been defined for XML, sinceXML itself is a subset appropriate to these Guidelines.

In the back matter, a bibliography lists works cited in the text of the Guidelines. A mechanicallygenerated index is also provided, which can serve, it is hoped, as a finding aid for the use of theGuidelines.

TEI Consortium 4 June 2004

1.1 Structure and Notational Conventions of this Document

1.1.2 Notational Conventions 1.1.2 Notational ConventionsThis section describes the typographic and stylistic conventions used throughout this document. The useof many terms and concepts which have not yet been defined is unavoidable in this section. All suchterms and concepts will be explained in later chapters of Part I.

When SGML or XML elements are mentioned in the text, they take the form , where “name”is the generic identifier of the element. Sample tags mentioned in the text are displayed in the form. References to attributes take the form attname, where“attname” is the name of the attribute. Where the elements and attributes thus mentioned are part of theTEI encoding scheme, they are included in the index.

These Guidelines distinguish encoding practices and elements as required, recommended, or optional.The phrases “must”, “is required to”, etc., mark practices and tags which are required for TEI con-formance. The phrases “should”, “it is recommended that”, “it is preferable to ...”, etc., are used indescribing practices which are recommended but not required for TEI conformance. Modal verbs like“may”, “might”, etc., mark practices which are strictly optional. Qualifying phrases like “if desired”,“where appropriate”, or “under some circumstances” are used when some tag or practice described maybe desirable or acceptable under some circumstances and not under others.

In the reference section in Part VII, elements and their attributes are all classed as one of:

required unconditionally required in a TEI-conformant documentmandatory when applicable required under the appropriate conditions; may be omitted if not

applicablerecommended recommended unless there are good reasons, in the given circumstances, against itrecommended when applicable recommended under some circumstances (which should be clear

from context)optional strictly optional

This reference section includes cross-references to the chapter or section of the main text within whicheach element is discussed. Most sections of the main text in which elements are defined begin with adescriptive list of the elements concerned in the following format:

short description of the element marked by . Where appropriate this is followed bya list of significant non-global attributes for the element as follows:

attribute description of the attribute’s meaning or usage, optionally followed by a list ofsuggested or legal values:value1 meaning of value1value2 meaning of value2

Not all attributes are always included in these lists; those which are shared with other elements in aclass are usually listed separately, and those of relatively specialized interest are usually listed only in thereference section. The values of the attribute are introduced with one of the following formulaic phrases:

‘Legal values include:’ The attribute cannot take values other than those given. Other values willcause parsing errors. (This is used relatively rarely in these Guidelines.)

‘Suggested values include:’ The values listed constitute a set which should suffice for mostpurposes, and they should be used where appropriate. Developers of TEI-aware softwareshould ensure that their software can process these values appropriately. In some cases,however, it is conceivable that other values might be necessary, so the declaration for theattribute does not restrict legal values to those given. TEI-aware software should havereasonable fallback processing for values not in the list.

‘Sample values include:’ The attribute can take any value; those listed are provided simply asexamples of the kind of value possible.



Each list of elements is followed by some discussion of its semantics and usage, followed by one or moreexamples, taken wherever possible from real texts, and presented in the following format:

This paragraph contains an italicized phrase

All the examples are (or should be) legal SGML or XML, but because they are fragmentary they maynot be parseable without additional context. They also frequently make liberal use of white space toexhibit the logical structure of the encoding more clearly. Although this does not affect the validity ofthe examples, some users will prefer not to follow it in practice, since not all processors will ignore theextra white space. Except where otherwise noted, examples do not use minimization not permitted byXML, though SGML users may wish to exercise SGML’s options to:

• use empty end-tags (of the form ) to close the most recently opened element• omit end-tags where they may legally be omitted (the TEI DTDs do not permit omission of

any start-tags)

Attribute values are given indifferently in single quotes or double quotes. Unquoted attribute values arenot permitted in XML, and so are not used except where otherwise noted, for example to emphasize acomparison between SGML and XML.

After the examples and usage notes, each section typically concludes with a DTD fragment containing theformal declarations for the elements described. Each DTD fragment is given a heading, and may containelement and attribute list declarations, entity declarations, parameter entity references, comments, andreferences to DTD fragments in other sections. The DTD fragments of a single chapter almost invariablybelong to the same DTD file, the structure of which is typically described (with references to the includedfragments) in one of the first or last sections of the chapter.

The DTD fragments are identical to the DTDs distributed with these Guidelines, with the followingexceptions:

• In the text, the DTD fragments appear in an order dictated by organization of this document;the actual DTD files may re-order the material slightly. This is indicated in the text byreferences from one DTD fragment to another.

• The DTD fragments in the text show the generic identifiers of all elements using the standardEnglish names assigned in this document; the actual DTD files use parameter entities for allgeneric identifiers, so that elements can be conveniently renamed, as described in chapter 29Modifying and Customizing the TEI DTD.

• The actual DTD files include conditional marked sections surrounding the element andattribute list declaration for each element, to ensure that elements can conveniently besuppressed or redefined, as described in chapter 29 Modifying and Customizing the TEI DTD.The fragments in the text suppress the marked-section-open and marked-section-close markup.

Note that, in both text and DTD, the omissibility indicators which must appear within an SGMLdeclaration (but which are illegal in XML) are always given in parameterized form, as in the followingexamples. This is to enable a single source to support both XML and SGML versions of the DTDs, asfurther discussed in section 3.8.4 Generation of an XML DTD.

What appears in the text, therefore, as:

will appear thus in the actual DTD file:

]]>

For further discussion, see chapter 3 Structure of the TEI Document Type Definition, or chapter 29Modifying and Customizing the TEI DTD.

1.2 Underlying Principles and Intended Use 1.2 Underlying Principles and Intended Use


1.2 Underlying Principles and Intended Use

1.2.1 Design Principles of the TEI Scheme 1.2.1 Design Principles of the TEI SchemeThe planning conference held at Vassar College in November, 1987 (see section 1.3 Historical Back-ground) agreed on a number of principles concerning the basic design goals of the Text Encoding Initia-tive. These principles are expounded in various documents of the TEI (notably TEI ED P1 and TEI EDP2) and the interested reader is directed to those documents for further discussion.

Because of its roots in the humanistic research community, the TEI scheme is driven by its original goal ofserving the needs of research, and is therefore committed to providing a maximum of comprehensibility,flexibility, and extensibility. More specific design goals of the TEI have been that the Guidelines should:

• provide a standard format for data interchange• provide guidance for encoding of texts in this format• support the encoding of all kinds of features of all kinds of texts studied by researchers• be application independent

This has led to a number of important design decisions, such as:

• the choice of SGML, XML, ISO 646, and Unicode• the provision of a large predefined tag set• a distinction between required, recommended, and optional encoding practices• encodings for different views of text• alternative encodings for the same text features• mechanisms for user-defined extensions to the scheme

These goals and principles are expounded in more detail below.

The goals of creating a common interchange format which is application independent require thedefinition of a specific markup syntax as well as the definition of a large predefined tag set. The syntaxof the recommendations made in this document conforms to the international standard ISO 8879, whichdefines the Standard Generalized Markup Language, and to the World Wide Web Consortium’s XMLRecommendation, which defines the Extensible Markup Language. Full document type declarations areprovided for the scheme described in these Guidelines; they are constructed so that they can be easilyconverted to either language. Reference is also made to ISO 646, which defines a standard seven-bitcharacter set; and to Unicode, which defines a larger character set supporting most modern languages.

The goal of providing guidance for text encoding requires that recommendations be made as to whattextual features should be recorded in various situations. This mandate is fulfilled by the explicitspecification, in the reference section for each tag, that the tag is required, mandatory when applicable butotherwise omissible, recommended generally, recommended when applicable but not always applicable,or optional.

However, the TEI Guidelines make (with relatively rare exceptions) no suggestions or restrictions as tothe relative importance of textual features. The philosophy of the Guidelines is “if you want to encodethis feature, do it this way” — but very few features are mandatory.

The Guidelines have been written largely with a focus on text capture (i.e. the representation in electronicform of an already existing copy text in another medium) rather than text creation (where no such copytext exists). Hence the frequent use of terms like ‘transcription’, ‘original’, ‘copy text’, etc. However,the Guidelines should be equally applicable to text creation, and the two terms text creation and textcapture are often used interchangeably.

Concerning text capture the TEI Guidelines do not specify a particular approach to the problem of fidelityto the source text and recoverability of the original; such a choice is the responsibility of the text encoder.The current version of these Guidelines, however, provides a more fully elaborated set of tags for markupof rhetorical, linguistic, and simple typographic characteristics of the text than for detailed markup ofpage layout or for fine distinctions among type fonts or manuscript hands.

In these Guidelines, no hard and fast distinction is drawn between ‘objective’ and ‘subjective’ informationor between ‘representation’ and ‘interpretation’. These distinctions, though widely made and oftenuseful in narrow, well-defined contexts, are perhaps best interpreted as distinctions between issues on



which there is a scholarly consensus and issues where no such consensus exists. Such consensushas been, and no doubt will be, subject to change. The TEI Guidelines do not make suggestions orrestrictions as to which of these features should be encoded. The use of the terms descriptive andinterpretive about different types of encoding in the Guidelines is not intended to support any particularview on these theoretical issues, but reflects a purely practical division of responsibility between thetwo committees called Committee on Text Representation and Committee on Text Interpretation andAnalysis.

In general, the accuracy and the reliability of the encoding and the appropriateness of the interpretationis for the individual user of the text to determine. The Guidelines provide a means of documentingthe encoding in such a way that a user of the text can know the reasoning behind that encoding, and thegeneral interpretive decisions on which it is based. It is strongly recommended that the TEI header beused to give an account of these aspects of the encoding. The TEI header is described in chapter 5 TheTEI Header.

In many situations more than one view of a text is needed. No absolute recommendation to embody onespecific view of text can apply to all texts and all approaches to them. The syntaxes of SGML and XMLensure that some encodings can be ignored for some purposes. To enable encoding multiple views, theseGuidelines not only treat a variety of text features, but sometimes provide several alternative encodingsfor what appear to be identical textual phenomena. These Guidelines therefore offer the possibility ofencoding many different views of the text, simultaneously if necessary.

However, the Guidelines are built on the assumption that there is a common core of textual features sharedby virtually all texts and virtually all serious work on texts. This core set of tags is defined in Chapter 6Elements Available in All TEI Documents. Beyond this core, many different elements can be encoded.

In brief, the TEI Guidelines define a general-purpose encoding scheme which makes it possible to encodedifferent views of text, possibly intended for different applications, serving the majority of scholarlypurposes of text studies in the humanities. However, no predefined encoding scheme can serve allresearch purposes. Therefore, the TEI also provides means of modifying and extending the encodingscheme defined by the Guidelines (see chapter 29 Modifying and Customizing the TEI DTD).

1.2.2 Intended Use 1.2.2 Intended UseWe envisage three primary functions for these Guidelines:

• guidance for individual or local practice in text creation and data capture;• support of data interchange;• support of application-independent local processing.

These three functions are so thoroughly interwoven in practice that it is hardly possible to address anyone without addressing the others. However, the distinction provides a useful framework for discussingthe possible role of the Guidelines in work with electronic texts.

1.2.2.1 Use in Text Capture and Text Creation 1.2.2.1 Use in Text Capture and Text CreationThe description of textual features found in the chapters which follow should provide a useful checklistfrom which scholars planning to create electronic texts should select the subset of features suitable fortheir project.

Problems specific to text creation or text ‘capture’ have not been considered explicitly in this document.For purposes of the TEI interchange format and for use of markup languages, it does not matter how atext is created or captured: it can be typed by hand, scanned from a printed book or typescript, read froma typesetter’s tape, or acquired from another researcher who may have used another markup scheme (orno explicit markup at all).

We include here only some general points which are often raised about markup and the process of datacapture.

XML, and even SGML, can appear distressingly verbose, particularly when (as in these Guidelines) thenames of tags and attributes are chosen for clarity and not for brevity. Editor macros and keyboardshorthands can allow a typist to enter frequently used tags with single keystrokes. Special-purpose


1.2 Underlying Principles and Intended Use

software may be purchased which scans word-processor or scanner data and inserts tags. Markup-aware software can help with maintaining the hierarchical structure of the document, and display thedocument with visual formatting rather than raw tags.

The techniques described in chapter 29 Modifying and Customizing the TEI DTD may be used to giveshorter names to the tags being used most often. It should also be noted that the examples in this text arechosen to exhibit the markup compactly, and thus have denser markup than will be typical in many texts.

The SGML standard provides ways of abbreviating, omitting, or otherwise minimizing the amount ofmarkup which need be explicitly provided in a text. They are all forbidden in the TEI interchange formatbecause their use complicates processing; this does not however preclude their use in local processing,where this is felt appropriate or desirable. The XML Working Group followed this guideline as well, andXML prohibits essentially the same minimization practices proposed by these Guidelines.

1.2.2.2 Use for Interchange 1.2.2.2 Use for InterchangeWhen the TEI Guidelines are used for interchange, it is expected that researchers using other encodingschemes in their work will translate outgoing data from such schemes into the scheme described bythese Guidelines, and similarly translate incoming data from the scheme described here into those usedinternally. For such translations to be carried out without loss of information, the scheme proposedhere must be as expressive (in a formal sense) as any encoding scheme now known to be in wide use fortextual research. To ensure that this is the case, a set of extension techniques is provided (see chapter 29Modifying and Customizing the TEI DTD) which makes possible the addition of extra tags, the renamingof existing tags, and certain kinds of redefinition. Although the intention is to minimize the need forrecourse to such extensions, they may be used to accommodate the encoding of new or unanticipatedtextual features. To translate between any pair of encoding schemes implies:

1. identifying the sets of textual features distinguished by the two schemes;2. determining where the two sets of features correspond;3. creating a suitable set of mappings.

For example, to translate from encoding scheme X into the TEI scheme:

1. Make a list of all the textual features distinguished in X.2. Identify the corresponding feature in the TEI scheme. There are three possibilities for each

feature:

i. the feature exists in both X and the TEI scheme;ii. X has a feature which is absent from the TEI scheme;

iii. X has a feature which corresponds with more than one feature in the TEI scheme.

The first case is unproblematic. The second requires an extension to the TEI scheme, asdescribed in chapter 29 Modifying and Customizing the TEI DTD. The third requires that aconsistent choice be made. The algorithm used to make that choice should be documented inthe TEI header.

3. Using the table of equivalences so generated, a simple translation can be carried out betweenX and the TEI.

The ease with which this translation can be carried out will of course depend on the clarity andexplicitness with which scheme X represents the features it encodes.

Translating from the TEI into scheme X follows the same pattern, except that if a TEI feature has noequivalent in X, and X cannot be extended, information must be lost in translation.

Similar procedures may be followed where the TEI scheme is to be used as an interlanguage forinterchange among several different sites or applications, although the degree of TEI-conformance mayvary.

In the simplest case, where two sites or individuals exchanging texts know each other and know orcan inquire what equipment the other is using, these Guidelines serve primarily as documentation for afile format, which can be referred to without actually being transmitted together with the file. In the



general case, where sender and recipient cannot communicate such information, a stricter degree of TEIconformance will be required for loss-free interchange.

The rules defining such strict conformance to the Guidelines are given in some detail in chapter 28Conformance. The interchange format defined there requires that an electronic text:

1. adhere to the SGML declaration defined in these Guidelines (when using SGML), or to theXML syntax rules (which imply a particular SGML declaration). These constructs are furtherdiscussed in chapter 2 A Gentle Introduction to XML.

2. conform to the document type declarations defined in these Guidelines, unless modifiedor extended as described in chapter 29 Modifying and Customizing the TEI DTD. Theseconstructs are further discussed in chapter 2 A Gentle Introduction to XML.3

3. provide external documentation as described in chapter 27 Tag Set Documentation for allelements not defined in these Guidelines, specifying a formal name (generic identifier) anda corresponding full natural-language name, describing its meaning and usage, specifying itslegal content and also any attributes it may use.

4. adhere to the requirements of the TEI header in providing bibliographic identification of thetext and description of the encoding practices used (as described in chapter 5 The TEI Header).

Note that the interchange format makes no formal restriction on the character set to be used in interchange,as this will depend on the medium of interchange and the local character sets in use by sender and receiver.For further information, refer to chapter 30 Rules for Interchange.

1.2.2.3 Use for Local Processing 1.2.2.3 Use for Local ProcessingMachine-readable text can be manipulated in many ways; some users:

• edit texts (e.g. word processors, syntax-directed editors)• edit, display, and link texts in hypertext systems• format and print texts using desktop publishing systems, or batch-oriented formatting pro-

grams• load texts into free-text retrieval databases or conventional databases• unload texts from databases as search results or for export to other software• search texts for words or phrases• perform content analysis on texts• collate texts for critical editions• scan texts for automatic indexing or similar purposes• parse texts linguistically• analyze texts stylistically• scan verse texts metrically• link text and images

These applications cover a wide range of likely uses but are by no means exhaustive. The aim has beento make the TEI Guidelines useful for encoding the same texts for different purposes. We have avoidedanything which would restrict the use of the text for other applications. We have also tried not to omitanything essential to any single application.

3 These guidelines do not provide any other schema (XML Schema, RELAX NG, etc.) corresponding to the DTDs, although suchmay be provided at a later time.


1.3 Historical Background

1.3 Historical Background 1.3 Historical BackgroundThe Text Encoding Initiative grew out of a planning conference sponsored by the Association forComputers and the Humanities (ACH) and funded by the U.S. National Endowment for the Humanities(NEH), which was held at Vassar College in November 1987. At this conference some thirtyrepresentatives of text archives, scholarly societies, and research projects met to discuss the feasibility ofa standard encoding scheme and to make recommendations for its scope, structure, content, and drafting.During the conference, the Association for Computational Linguistics and the Association for Literaryand Linguistic Computing agreed to join ACH as sponsors of a project to develop the Guidelines. Theoutcome of the conference was this set of principles, which determined the further course of the project.

1. The guidelines are intended to provide a standard format for data interchange in humanitiesresearch.

2. The guidelines are also intended to suggest principles for the encoding of texts in the sameformat.

3. The guidelines should

i. define a recommended syntax for the format,ii. define a metalanguage for the description of text-encoding schemes,

iii. describe the new format and representative existing schemes both in that metalan-guage and in prose.

4. The guidelines should propose sets of coding conventions suited for various applications.5. The guidelines should include a minimal set of conventions for encoding new texts in the

format.6. The guidelines are to be drafted by committees on

i. text documentationii. text representation

iii. text interpretation and analysisiv. metalanguage definition and description of existing and proposed schemes,

coordinated by a steering committee of representatives of the principal sponsoring organiza-tions.

7. Compatibility with existing standards will be maintained as far as possible.8. A number of large text archives have agreed in principle to support the guidelines in their

function as an interchange format, and have (since the publication of the prior edition), actuallydone so. We continue to encourage funding agencies to support development of tools tofacilitate this interchange.

9. Conversion of existing machine-readable texts to the new format involves the translation oftheir conventions into the syntax of the new format. No requirements will be made for theaddition of information not already coded in the texts.

In the course of the work, some of these goals assumed greater, some lesser importance; some provedeasier, some harder to achieve. The document in hand does define a standard form for the interchangeof textual material, and adumbrate principles for the creation of new electronic texts. The onlymetalanguage used, however, is that common to XML and SGML, and no formal definitions are given forother encoding schemes. These Guidelines do define a minimal set of conventions for text encoding (i.e.those elements classed as recommended or required), though few researchers will be satisfied to encodeonly what is required or recommended here, since the set of required and recommended elements is rathersmall. This document does not, however, define — at least not explicitly — “sets of coding conventionssuited for various applications”, since consensus on suitable conventions for different applications provedelusive; this remains a goal for future work.

1.3.1 Origin and Development of the TEI 1.3.1 Origin and Development of the TEIThe Text Encoding Initiative proper began in June 1988 with funding from the NEH, soon followed byfurther funding from the Commission of the European Communities, the Andrew W. Mellon Foundation,and the Social Science and Humanities Research Council of Canada. Four working committees,composed of distinguished scholars and researchers from both Europe and North America, were namedto deal with problems of text documentation (resulting largely in chapter 5 The TEI Header), textrepresentation, text analysis and interpretation (together responsible for most of what has become partsII, III, and IV), and metalanguage and syntax issues (largely responsible for part VI).A first draft version (1.0) of the Guidelines was distributed in July 1990 under the title Guidelines for theEncoding and Interchange of Machine-Readable Texts, with the TEI document number TEI P1. Withminor changes and corrections, this version was reprinted as version 1.1 in November 1990.Extensive public comment and further work on areas not covered in version 1 resulted in the drafting ofa revised version, TEI P2, distribution of which began in April 1992. This version includes substantialamounts of new material, resulting from work carried out by several specialist working groups, set up in1990 and 1991 to propose extensions and revisions to the text of P1. The overall organization, both ofthe draft itself and of the scheme it describes, was entirely revised and reorganized in response to publiccomment on the first draft.In June, 1993, the Advisory Board of the Text Encoding Initiative met to review the current state of theGuidelines, and recommended the formal publication of the work done to that time. That version ofthe TEI Guidelines, TEI P3, represents a further revision of all chapters published under the documentnumber TEI P2, and the addition of further chapters. Although subject to revision and amendment onthe basis of practical experience and public discussion, that version of the Guidelines was published inMay of 1994 without the label ‘draft’, and marks the conclusion of the initial development work.In February of 1998 the World Wide Web Consortium issued a final Recommendation for the ExtensibleMarkup Language, XML. XML was developed as a far simpler subset of SGML, for many of the samereasons as the TEI interchange subset, and taking a very similar approach. Several TEI participantscontributed heavily to the development of XML, most notably XML’s senior co-editor C. M. Sperberg-McQueen, who until recently served as the North American co-editor for these Guidelines.Following the ratification of XML and its rapid adoption, many projects found need for an updated versionof these Guidelines which supported XML unambiguously. For example, because SGML element namesare normally case-insensitive while XML ones are not, a decision had to be made on the normativecase for TEI element names in XML. The TEI editors, with abundant assistance from others who havedeveloped and used TEI, developed an update plan, and made tentative decisions on relevant syntacticissues. With the formation of the TEI Consortium in 2001, and with generous funding from the NationalEndowment for the Humanities, a formal update was undertaken. The goals of this update were to reviseboth the text and the DTDs of the scheme in a way compatible with the use of either SGML or XML. Thepresent edition is the first public draft of that update; the present editors hope that it maintains the qualityand usefulness of P3, and solicit comments, suggestions, and other input wherever it does not.



1.3.2 Future Developments 1.3.2 Future DevelopmentsWork on areas still not satisfactorily covered in this manual will continue, and resulting recommendationswill be issued as supplements to the published Guidelines. Work is expected to continue in at least thefollowing areas:

• linguistic description and grammatical annotation• historical analysis and interpretation• base tag sets for further document types• manuscript analysis and physical description of text

The encoding recommended by this document may be used without fear that future versions of the TEIscheme will be inconsistent with it in fundamental ways. The TEI will be sensitive, in revising theseGuidelines, to the possible problems which revision might pose for those who are already using thisversion of the Guidelines. Wherever consistent with the long-term goals of the project, consistency withthis version will be preserved in future revisions.


2 A Gentle Introduction to XML 2 A Gentle Introduction to XMLAs originally published in previous editions of the Guidelines, this chapter provided a gentle introduction to ‘just enough’SGML for anyone to understand how the TEI used that standard. Since then, the Gentle Guide seems to have taken on a lifeof its own independent of the Guidelines, having been widely distributed (and flatteringly imitated) on the web. In revisingit for the present draft, the editors have therefore felt free to reduce considerably its discussion of SGML-specific matters, infavour of a simple presentation of how the TEI uses XML.

The encoding scheme defined by these Guidelines may be formulated either as an application of the ISOStandard Generalized Markup Language (SGML)4 or of the more recently developed W3C ExtensibleMarkup Language (XML)5. Both SGML and XML are widely-used for the definition of device-independent, system-independent methods of storing and processing texts in electronic form; XML beingin fact a simplification or derivation of SGML. In the present chapter we introduce informally the basicconcepts underlying such markup languages and attempt to explain to the reader encountering themfor the first time how they are actually used in the TEI scheme. Except where the two are explicitlydistinguished, references to XML in what follows may be understood to apply equally well to the TEIusage of SGML. For a more technical account of TEI practice see chapter 28 Conformance; for a moretechnical description of the subset of SGML used by the TEI encoding scheme, see chapter 39 FormalGrammar for the TEI-Interchange-Format Subset of SGML.

XML is an extensible markup language used for the description of marked-up electronic text. Moreexactly, XML is a metalanguage, that is, a means of formally describing a language, in this case, amarkup language. Historically, the word markup has been used to describe annotation or other markswithin a text intended to instruct a compositor or typist how a particular passage should be printed or laidout. Examples include wavy underlining to indicate boldface, special symbols for passages to be omittedor printed in a particular font and so forth. As the formatting and printing of texts was automated, theterm was extended to cover all sorts of special codes inserted into electronic texts to govern formatting,printing, or other processing.

Generalizing from that sense, we define markup, or (synonymously) encoding, as any means of makingexplicit an interpretation of a text. Of course, all printed texts are implicitly encoded (or marked up)in this sense: punctuation marks, use of capitalization, disposition of letters around the page, even thespaces between words, might be regarded as a kind of markup, the function of which is to help the humanreader determine where one word ends and another begins, or how to identify gross structural featuressuch as headings or simple syntactic units such as dependent clauses or sentences. Encoding a text forcomputer processing is in principle, like transcribing a manuscript from scriptio continua,6 a process ofmaking explicit what is conjectural or implicit, a process of directing the user as to how the content ofthe text should be (or has been) interpreted.

By markup language we mean a set of markup conventions used together for encoding texts. Amarkup language must specify what markup is allowed, what markup is required, how markup is tobe distinguished from text, and what the markup means. XML provides the means for doing the firstthree; documentation such as these Guidelines is required for the last.

The present chapter attempts to give an informal introduction to those parts of XML of which a properunderstanding is necessary to make best use of these Guidelines. The interested reader should also consultone or more of the dozens of excellent introductory text books or web sites now available on the subject.

4 International Organization for Standardization, ISO 8879: Information processing – Text and office systems – StandardGeneralized Markup Language (SGML), ([Geneva]: ISO, 1986).5 World Wide Web Consortium: Extensible Markup Language (XML) 1.0, available from http://www.w3.org/TR/REC-xml6 In the “continuous writing” characteristic of manuscripts from the early classical period, words are written continuously with nointervening spaces or punctuation.


http://www.w3.org/TR/REC-xml

2 A Gentle Introduction to XML

2.1 What’s special about XML? 2.1 What’s special about XML?Three characteristics of XML seem to us to make it unlike other other markup languages:

• its emphasis on descriptive rather than procedural markup;• its document type concept;• its independence of any one hardware or software system.

These three aspects are discussed briefly below, and then in more depth in sections 2.3 XML structuresand 2.7 Entities.The markup language with which XML is most frequently compared, however, is HTML, the language inwhich web pages had always been written until XML began to replace it. Compared with HTML, XMLhas some other important characteristics:

• XML is extensible: it does not contain a fixed set of tags• XML documents must be well-formed according to a defined syntax, and may be formally

validated• XML focuses on the meaning of data, not its presentation

2.1.1 Descriptive markup 2.1.1 Descriptive markupIn a descriptive markup system, the markup codes used do little more than categorize parts of a document.Markup codes such as or \end{list} simply identify a portion of a document and assert of itthat “the following item is a paragraph,” or “this is the end of the most recently begun list,” etc. Bycontrast, a procedural markup system defines what processing is to be carried out at particular points ina document: “call procedure PARA with parameters 1, b and x here” or “move the left margin 2 quadsleft, move the right margin 2 quads right, skip down one line, and go to the new left margin,” etc. InXML, the instructions needed to process a document for some particular purpose (for example, to formatit) are sharply distinguished from the descriptive markup which occurs within the document. Theyare collected outside the document in separate procedures or programs, and are usually expressed in adistinct document called a stylesheet, though it may do much more than simply define the rendition orvisual appearance of a document.7

With descriptive instead of procedural markup the same document can readily be processed in manydifferent ways, using only those parts of it which are considered relevant. For example, a contentanalysis program might disregard entirely the footnotes embedded in an annotated text, while a formattingprogram might extract and collect them all together for printing at the end of each chapter. Different kindsof processing can be carried out with the same part of a file. For example, one program might extractnames of persons and places from a document to create an index or database, while another, operatingon the same text, but using a different stylesheet, might print names of persons and places in a distinctivetypeface.

2.1.2 Types of document 2.1.2 Types of documentA second key aspect of XML is its notion of a document type: documents are regarded as having types,just as other objects processed by computers do. The type of a document is formally defined by itsconstituent parts and their structure. The definition of a ‘report’, for example, might be that it consistedof a ‘title’ and possibly an ‘author’, followed by an ‘abstract’ and a sequence of one or more ‘paragraphs’.Anything lacking a title, according to this formal definition, would not formally be a report, and neitherwould a sequence of paragraphs followed by an abstract, whatever other report-like characteristics thesemight have for the human reader.If documents are of known types, a special purpose program (called a parser), once provided with anunambiguous definition of a document’s type, can check that any document claiming to be of a that typedoes in fact conform to the specification. A parser can check that all and only elements specified for aparticular document type are present, that they are combined in appropriate ways, correctly ordered andso forth. More significantly, different documents of the same type can be processed in a uniform way.Programs can be written which take advantage of the knowledge encapsulated in the document structureinformation, and which can thus behave in a more ‘intelligent’ fashion.7 We do not here discuss in any detail the ways that a style sheet can be used or defined, nor do we discuss the increas-ingly popular W3C Stylesheet Languages. See http://www.w3.org/TR/xsl for the Extensible Stylesheet Language (XSL), andhttp://www.w3.org/TR/xslt for the XSL Transformations (XSLT) Language.


http://www.w3.org/TR/xslhttp://www.w3.org/TR/xslt

2.2 Textual structure

2.1.3 Data independence 2.1.3 Data independenceA basic design goal of XML is to ensure that documents encoded according to its provisions can movefrom one hardware and software environment to another without loss of information. The two featuresdiscussed so far both address this requirement at an abstract level; the third feature addresses it at thelevel of the strings of data characters of which documents are composed. All XML documents, whateverlanguage or writing system they employ, use the same underlying character encoding (that is, the samemethod of representing the graphic forms making up a particular writing system as binary data).8 Thisencoding is defined by an international standard,9 which is implemented by a universal character setmaintained by an industry group called the Unicode Consortium, and known as Unicode;10 this providesa standardised way of representing any of the thousands of discrete symbols making up the world’swriting systems, past and present.For technical and historical reasons which need not concern us, it is often necessary to translate textsencoded as Unicode into some smaller or less general encoding scheme. XML uses a general purposestring substitution mechanism for this purpose, inherited from SGML (which predates the availability ofUnicode). In simple terms, this mechanism allows for the indirect representation of arbitrary parts of adocument (be they single characters, character strings, or whole files) within it. One obvious applicationfor this mechanism is to ensure consistency of nomenclature; another, more significant one, is to counterthe notorious inability of different computer systems to understand each other’s character sets, or of anyone system to provide all the graphic characters needed for a particular application. The strings defined bythis string-substitution mechanism are called entities and they are discussed below in section 2.7 Entities.

2.2 Textual structure 2.2 Textual structureA text is not an undifferentiated sequence of words, much less of bytes. For different purposes, it maybe divided into many different units, of different types or sizes. A prose text such as this one might bedivided into sections, chapters, paragraphs, and sentences. A verse text might be divided into cantos,stanzas, and lines. Once printed, sequences of prose and verse might be divided into volumes, gatherings,and pages.Structural units of this kind are most often used to identify specific locations or reference points within atext (“the third sentence of the second paragraph in chapter ten”; “canto 10, line 1234”; “page 412,” etc.)but they may also be used to subdivide a text into meaningful fragments for analytic purposes (“is theaverage sentence length of section 2 different from that of section 5?” “how many paragraphs separateeach occurrence of the word ‘nature’?” “how many pages?”). Other structural units are more clearlyanalytic, in that they characterize a section of a text. A dramatic text might regard each speech by adifferent character as a unit of one kind, and stage directions or pieces of action as units of another kind.Such an analysis is less useful for locating parts of the text (“the 93rd speech by Horatio in Act 2”) thanfor facilitating comparisons between the words used by one character and those of another, or those usedby the same character at different points of the play.In a prose text one might similarly wish to regard as units of different types passages in direct or indirectspeech, passages employing different stylistic registers (narrative, polemic, commentary, argument, etc.),passages of different authorship and so forth. And for certain types of analysis (most notably textualcriticism) the physical appearance of one particular printed or manuscript source may be of importance:paradoxically, one may wish to use descriptive markup to describe presentational features such astypeface, line breaks, use of whitespace and so forth.These textual structures overlap with each other in complex and unpredictable ways. Particularly whendealing with texts as instantiated by paper technology, the reader needs to be aware of both the physicalorganization of the book and the logical structure of the work it contains. Many great works (Sterne’sTristram Shandy for example) cannot be fully appreciated without an awareness of the interplay betweennarrative units (such as chapters or paragraphs) and page divisions. For many types of research, it is theinterplay between different levels of analysis which is crucial: the extent to which syntactic structureand narrative structure mesh, or fail to mesh, for example, or the extent to which phonological structuresreflect morphology.

8 See Extensible Markup Language (XML) 1.0, Section 2.2 Characters.9 ISO/IEC 10646-1993 Information Technology — Universal Multiple-Octed Coded Character Set (UCS)10 See http://www.unicode.org/


http://www.unicode.org/


2.3 XML structures 2.3 XML structuresThis section describes the simple and consistent mechanism for the markup or identification of textualstructure provided by XML. It also describes the methods XML provides for the expression of rulesdefining how units of textual structure can meaningfully be combined in a text.

2.3.1 Elements 2.3.1 ElementsThe technical term used in XML for a textual unit, viewed as a structural component, is element.Different types of elements are given different names, but XML provides no way of expressing themeaning of a particular type of element, other than its relationship to other element types. That is,all one can say about an element called (for instance) is that instances of it may (or may not)occur within elements of type , and that it may (or may not) be decomposed into elements oftype . It should be stressed that XML is entirely unconcerned with the semantics of textualelements: these are application dependent. It is up to the creators of XML vocabularies (such as theseGuidelines) to choose intelligible names for the elements they identify and to define their proper use intext markup. That is the chief purpose of documents such as the TEI Guidelines. From the need tochoose element names indicative of function comes the technical term for the name of an element type,which is generic identifier, or GI.

Within a marked up text (a document instance), each element must be explicitly marked or tagged insome way. This is done by inserting a tag at the beginning of the element (a start-tag) and another atits end (an end-tag).11 The start- and end-tag pair are used to bracket off the element occurrences withinthe running text, in rather the same way as different types of parentheses or quotation marks are used inconventional punctuation. For example, a quotation element in a text might be tagged as follows:

... Rosalind's remarks This is the silliest stuffthat ere I heard of! clearly indicate ...

As this example shows, a start-tag takes the form , where the opening angle bracket indicatesthe start of the start-tag, “quote” is the generic identifier of the element which is being delimited, andthe closing angle bracket indicates the end of a tag. An end-tag takes an identical form, except that theopening angle bracket is followed by a solidus (slash) character, so that the corresponding end-tag is.12

2.3.2 Content models: an example 2.3.2 Content models: an exampleAn element may be empty, that is, it may have no content at all, or it may contain just a sequence ofcharacters with no other elements. More usually, however, elements of one type will be embedded(contained entirely) within elements of a different type.

To illustrate this, we will consider a very simple structural model. Let us assume that we wish to identifywithin an anthology only poems, their titles, and the stanzas and lines of which they are composed. InXML terms, our document type is the anthology, and it consists of a series of poems. Each poem hasembedded within it one element, a title, and several occurrences of another, a stanza, each stanza havingembedded within it a number of line elements. Fully marked up, a text conforming to this model mightappear as follows:13

The SICK ROSE

O Rose thou art sick.The invisible worm,That flies in the night

11 In SGML (but not in XML) the name and the content model may be separated by an additional part of the declaration whichspecifies ‘omission rules’ for the element concerned. These rules state whether or not start- and end-tags must be present for everyoccurrence of the element concerned: as noted above, such tag omission is not permitted in XML, and is not permitted in the TEIInterchange format.12 Because the opening angle bracket has this special function in an XML document, special steps must be taken to use thatcharacter for other purposes (for example, as the mathematical less-than operator); see further 2.7.2 Entity references; in SGML(but not XML) different characters may be defined for use as any of the delimiting characters (the angle brackets, exclamation markand solidus).13 The example is taken from William Blake’s Songs of innocence and experience (1794). The markup is designed for illustrativepurposes and is not TEI-conformant.


2.3 XML structures

In the howling storm:

Has found out thy bedOf crimson joy:And his dark secret loveDoes thy life destroy.

It should be stressed that this example does not use the same names as are proposed for correspondingelements elsewhere in these Guidelines: the above is not a valid TEI document. It will however serve asan introduction to the basic notions of XML. Whitespace and line breaks have been added to the examplefor the sake of visual clarity only; they have no particular significance in the XML encoding itself. Also,the line

is an XML comment and is not treated as part of the text.

As it stands, the above example is what is known as a well-formed XML document: to achieve this status,an XML document must obey the following simple rules:

• there should be a single element (start- and end- tag pair) which encloses the whole document:this is known as the root element ( in our case);

• each element should be completely contained by the root element, or by an element which isso contained; elements may not partially overlap one another;

• the tags marking the start and end of each element must always be present. 14

An XML document which is well-formed can be processed in a number of useful ways. A simpleindexing program could extract only the relevant text elements in order to make a list of titles, first lines,or words used in the poem text; a simple formatting program could insert blank lines between stanzas,perhaps indenting the first line of each, or inserting a stanza number. Different parts of each poem couldbe typeset in different ways. A more ambitious analytic program could relate the use of punctuationmarks to stanzaic and metrical divisions.15 Scholars wishing to see the implications of changing thestanza or line divisions chosen by the editor of this poem can do so simply by altering the position of thetags. And of course, the text as presented above can be transported from one computer to another andprocessed by any program (or person) capable of making sense of the tags embedded within it with noneed for the sort of transformations and translations needed to move word processor files around.

However, well-formedness alone is not enough for the full range of what might be useful in marking up adocument. It might well be useful if, in the process of preparing our digital anthology, a computer systemcould check some basic rules about how stanzas, lines, and titles can sensibly co-occur in a document.It would be even more useful if the system could check that stanzas are always labelled andnot occasionally or . An XML document in which such rules have been checkedis technically known as a valid document, and the ability to perform such validation is one of the keyadvantages of using XML. To carry this out, some way of formally stating the criteria for successfulvalidation is necessary: in XML this formal statement may be provided by an additional document knownas a document type declaration (DTD) or by an XML schema.16

14 This is not strictly true for empty elements, for which start- and end-tags can be combined, as further discussed below.15 Note that this simple example has not addressed the problem of marking elements such as sentences explicitly; the implicationsof this are discussed below in section 2.5 Complicating the issue.16 The DTD language described in the remainder of this section is neither the only way of representing such criteria, northe most powerful. One important alternative is provided by another W3C Recommendation: the XML Schema language(http://www.w3.org/XML/Schema); another is provided by the OASIS Committee’s specification for Relax NG (http://www.oasis-open.org/committees/relax-ng/). It is highly probable that future releases of these Guidelines will use such a language, in preferenceto, or as well as, a DTD.


http://www.w3.org/XML/Schemahttp://www.oasis-open.org/committees/relax-ng/http://www.oasis-open.org/committees/relax-ng/


2.4 Validating a document’s structure 2.4 Validating a document’s structureRules such as those informally stated above are the first stage in the creation of a formal specificationfor the structure of an XML document, or document type declaration, usually abbreviated to DTD. Increating a DTD, the document designer may be as lax or as restrictive as the occasion warrants. A balancemust be struck between the convenience of following simple rules and the complexity of handling realtexts. This is particularly the c