|TITLE:||ISO 8879 TC 2|
|PROJECT EDITOR:||Charles F. Goldfarb|
|STATUS:||Approved text, Alexandria VA, USA|
|ACTION:||For publication by ITTF|
|SUMMARY OF MAJOR POINTS:||This Technical Corrigendum adds a normative annex K and an informative annex L to ISO 8879.|
|DATE:||4 December 1997|
|DISTRIBUTION:||WG4 members and liaisons|
|REFER TO:||ISO 8879|
|REPLYTO:||Dr. James D. Mason
(ISO/IEC JTC1/WG4 Convenor)
Lockheed Martin Energy Systems
Information Management Services
1060 Commerce Park
Oak Ridge, TN 37830 U.S.A.
Telephone: +1 423 574-6973
Facsimile: +1 423 574-6983
All occurrences of "element declaration" in this International Standard are changed to "element type declaration".
All occurrences of "element set" in this International Standard are changed to "element type set".
Replace 4.223 with:
4.223 owner identifier: The portion of a public identifier that identifies its owner.
Note: The owner of a public identifier is not necessarily the owner of the object that it identifies.
Add the following normative annex K and informative annex L to ISO 8879.
This annex remedies defects revealed by the multiple adaptations of SGML for the World Wide Web (WWW), intranets, and extranets. The annex corrects errors, resolves ambiguities for which there is a clear resolution that does not cause existing conforming documents to become non-conforming, and provides a choice of alternative resolutions for other ambiguities. Although motivated by the World Wide Web, applicability of this annex extends to all uses of SGML.
This annex makes reference to groves and property sets, which are defined in the SGML Extended Facilities of the 2nd Edition of HyTime (ISO/IEC 10744) and also in DSSSL (ISO/IEC 10179).
The decision to conform to this annex is made for individual documents and is indicated in the SGML declaration, as described below (K.3.2). An SGML system need not support this annex in order to be a conforming SGML system.
This annex is organized as a set of replacement and new syntax productions, and is phrased in terms of modifications to be made to the body of this International Standard. However, these modifications are applicable only when conforming to this annex.
An SGML parser that supports this annex shall be able to parse conforming SGML documents that do not claim conformance to it. The parsing of such documents must produce the same grove as would a conforming SGML parser that does not support this annex. Error reporting for such documents, however, is with respect to the standard as modified by this annex; errors with respect to the unmodified standard need not be reported.
Markup declarations that occur in the external and internal subsets of document type declarations.
The portion of a document type declaration subset referenced by the external identifier parameter of a document type declaration.
The portion of a document type declaration subset that occurs between the dso and dsc of a document type declaration.
If the dso and dsc are omitted, the internal subset is empty (rather than non-existent).
An SGML document that complies with all provisions of this International Standard.
Note 1: The provisions allow for choices in the use of options, features, and variant concrete syntaxes.
A conforming SGML document must be a type-valid SGML document, a fully-tagged SGML document, or both.
Note 2: A user may wish to enforce additional constraints on a document, such as whether a document instance is integrally-stored or free of entity references.
An SGML document in which, for each document instance, there is an explicitly associated document type declaration to whose DTD that instance conforms.
An SGML document, all of whose document instances are fully-tagged. There need not be a document type declaration associated with any of the instances.
Note 3: If there is a document type declaration, it must conform to the provisions that apply to them.
A document instance in which a start-tag with a generic identifier, and an end-tag, are present for every element, and the attribute name is present in every attribute specification in the start-tag.
Note 4: An SGML system that supports unconstrained SGML documents must be able to parse DTD declarations and resolve both internal and external entity references. If it continues parsing (as a form of error-recovery) after failing to access a referenced entity, the results are unpredictable. Observing one or more of the entity constraints defined in this International Standard may cause a document to be more amenable to processing by a simpler SGML system, or in an environment (such as a network) where access to external entities may be slow or unreliable.
A document instance in which every element and marked section ends in the entity in which it begins.
Note 5: This constraint makes it possible, as a form of error-recovery, for parsing to continue in a fully-tagged document instance after a failure to access a referenced entity. The resulting grove will be the same for the parsed text, except for the tree addresses of younger siblings of the nodes in the inaccessible entity. The constraint also has implementation benefits for editors, "lazy" replacement of entity references, and sharing of grove portions when entities are reused.
An SGML document that has no entity references other than references to predefined data character entities.
Note 6: A reference-free document can be parsed by conforming SGML systems that cannot resolve entity references.
An SGML document that has no external entity references.
Note 7: An external-reference-free document could have attribute values that contain names of external entities or that otherwise might cause an application to access an external entity by means other than entity references.
Note 8: External-reference-free documents can be parsed by systems that cannot resolve external entity-references.
A general entity, associated with a character number in the syntax-reference character set, that is used to reference significant SGML characters as data.
Note 9: In order to allow delimiter escaping when parsing without respect to DTD declarations, there should be a predefined data character entity for the first character of each delimiter string that can be recognized in a mode where data can occur.
The characters assigned to the SEPCHAR, SPACE, RE, and RS functions.
 SGML declaration = "<!SGML", ps+, (SGML declaration body | SGML declaration reference), ps*, ">"
In order for SGML documents to be self-identifying, it is strongly recommended that all conforming SGML documents contain one of the forms of SGML declaration.
[171.2] SGML declaration reference = name, external identifier? where: "name" is a name in the reference concrete syntax. "external identifier" must reference an SGML declaration body. If omitted, the external identifier is "SYSTEM".
A public identifier, if formal, shall use the public text class (10.2.2.1) "SD" to identify an SGML declaration body.
Note 10: For example:
<!SGML HTML3.2 PUBLIC "+//IDN W3C.ORG//SD HTML Version 3.2//EN">
[171.1] SGML declaration body = minimum literal, ps+, document character set, ps+, capacity set, ps+, concrete syntax scope, ps+, concrete syntax, ps+, feature use, ps+, application-specific information, (ps+, added requirements)?
The minimum data of the minimum literal shall be one of the following:
The ENR suffix indicates that the document conforms to Annex J of this International Standard.
The WWW suffix indicates that the document conforms to Annex K (this annex) of this International Standard, which incorporates by reference the provisions of Annex J of this International Standard and supersedes any contradictory provisions elsewhere in this International Standard.
Note 11: Certain parameters of the SGML declaration body are omissible in order to allow existing documents to conform to this annex by a simple change to the minimum data. Nevertheless, it is recommended that all parameters be specified.
 capacity set = "CAPACITY", ps+, (("PUBLIC", ps+, public identifier)| "NONE"| ("SGMLREF", (ps+, name, ps+, number)*))
NONE indicates that no capacities are specified.
Specifying NONE does not require a system to support capacities greater than those specified in its system declaration.
 concrete syntax = "SYNTAX", ps+, (public concrete syntax | (shunned character number identification, ps+, syntax-reference character set, ps+, function character identification, ps+, naming rules, ps+, delimiter set, ps+, reserved name use, ps+, quantity set, (ps+, predefined data character entities)?))
 quantity set = "QUANTITY", ps+, ("NONE"| ("SGMLREF", (ps+, name, ps+, number)*))
NONE indicates that no quantities are specified.
Specifying NONE does not require a system to support quantities greater than those specified in its system declaration.
[194.1] predefined data character entities = "ENTITIES", ps+, ("NONE"|(parameter literal, ps+, character number)+)
Each interpreted "parameter literal" must be a valid general entity name in the syntax being defined, and is associated with a character number in the syntax-reference character set. When the named entity is referenced, the replacement text is a numeric character reference to the corresponding character. Predefined data character entities are treated as though defined at the start of the internal subset of all documents in which the concrete syntax is used.
Note 12: For example:
ENTITIES "amp" 38 "lt" 60 "gt" 62 "quot" 34 "apos" 39
 markup minimization features = "MINIMIZE", ps+, "DATATAG", ps+, ("NO"|"YES"), ps+, "OMITTAG", ps+, ("NO"|"YES"), ps+, "RANK", ps+, ("NO"|"YES"), ps+, ("SHORTTAG", ps+, ("NO"|"YES"| (start-tag options, end-tag options, attribute-options))), (ps+, empty element ending rules, ps+, implicit definitions)?
[196.1] start-tag options = "STARTTAG", ps+, "EMPTY", ps+, ("NO"|"YES"), ps+, "UNCLOSED", ps+, ("NO"|"YES"), ps+, "NETENABL", ps+, ("NO"|"ALL"|"IMMEDNET") where: EMPTY enables empty start-tags. UNCLOSED enables unclosed start-tags. NETENABL permits NET-enabling start-tags and NULL end-tags, and IMMEDNET restricts them to elements with empty syntactic content that must be ended by a NET; it cannot be specified if EMPTYNRM NO is specified.
Note 13: An element with empty syntactic content need not have been declared EMPTY.
[196.2] end-tag options = "ENDTAG", ps+, "EMPTY", ps+, ("NO"|"YES"), ps+, "UNCLOSED", ps+, ("NO"|"YES") where: EMPTY enables empty end-tags. UNCLOSED enables unclosed end-tags.
[196.3] attribute options = "ATTRIB", ps+, "DEFAULT", ps+, ("NO"|"YES"), ps+, "OMITNAME", ("NO"|"YES"), ps+, "VALUE", ps+, ("NO"|"YES") where: DEFAULT enables attribute value defaulting (18.104.22.168). OMITNAME allows attribute names and vi to be omitted for unique NMTOKEN values (22.214.171.124). VALUE allows some attribute values to be specified without delimiters, rather than as literals (126.96.36.199).
[196.4] empty element ending rules = "EMPTYNRM", ps+, ("NO"|"YES"), ps+, where: EMPTYNRM applies normal rules for the presence of end-tags, including markup minimization rules, to elements of a type declared EMPTY, or that are forced to be EMPTY by an explicit content reference attribute (7.3.).
[196.5] implicit definitions = "IMPLYDEF", ps+, "ATTLIST", ps+, ("NO"|"YES"), ps+, "DOCTYPE", ps+, ("NO"|"YES") "ELEMENT", ps+, ("NO"|"YES"), ps+, "ENTITY", ps+, ("NO"|"YES"), ps+, "NOTATION", ps+, ("NO"|"YES"), ps+, where: ATTLIST means an undeclared attribute is defined as: CDATA #IMPLIED; however, no attribute assignment node is created for an attribute unless that attribute was specified. DOCTYPE means that a document instance with no associated document type declaration is treated as though the declaration were <!DOCTYPE #IMPLIED SYSTEM [ ]> ELEMENT means an undeclared element type is defined as: - - ANY ENTITY means an undeclared general entity is defined as: SYSTEM NOTATION means an undeclared notation is defined as: SYSTEM
IMPLYDEF allows the specified constructs to be used without an explicit declaration.
When IMPLYDEF ENTITY is specified, #DEFAULT cannot be specified as a general entity name.
Note 14: IMPLYDEF DOCTYPE cannot be specified if the explicit link or concur features are in use.
Implicit definitions occur in the grove in the order in which it is necessary to imply them.
Note 15: An implicit definition does not reflect any explicit definition that was not respected during parsing (K.4.9), nor does it constrain any that might be declared in the future.
 other features = "OTHER", ps+, "CONCUR", ps+, ("NO"|"YES"), ps+, "SUBDOC", ps+, ("NO"|"YES"), ps+, "FORMAL", ps+, ("NO"|"YES"), (urn feature, keeprsre feature, validity feature, entities feature)?
[198.1] urn feature = ps+, "URN", ps+, ("NO"|"YES") where: URN means public identifiers are interpreted according to the applicable Internet Engineering Task Force RFC2141 governing Universal Resource Names. If both URN and FORMAL are YES, public identifiers are interpreted either as formal public identifiers or as URNs.
[198.2] keeprsre feature = ps+, "KEEPRSRE", ps+, ("YES"|"NO") where: KEEPRSRE means clause 7.6.1 does not apply.
Note 16: If KEEPRSRE YES is specified, all white space in mixed content is included in the grove as datachar nodes.
Note 17: This option does not affect delimited strings, such as attribute value literals, which have their own rules for normalizing white space (and which, in any case, do not occur in content).
[198.3] validity feature = ps+, "VALIDITY", ps+, ("NOASSERT"|"TYPE"|"TAG"|"TYPE-TAG") where: VALIDITY asserts whether the document is TYPE-valid, fully-TAGged or both (TYPE-TAG), or makes no validity assertion (NOASSERT). It is a reportable markup error if an assertion is untrue. If the VALIDITY parameter is omitted, TYPE is assumed. [198.4] entities feature = ps+, "ENTITIES", ps+, ("NOASSERT"| ("REF", ps+, ("NONE"|"INTERNAL"|"ANY"), ps+, "INTEGRAL", ps+, ("NO"|"YES"))) where: ENTITIES makes entity constraint assertions or does not (NOASSERT). INTEGRAL means document instances are integrally-stored. REF means the document has unconstrained entity references (ANY), is external-reference-free (INTERNAL), or is reference-free (NONE). If the ENTITIES parameter is omitted, NOASSERT is assumed.
Note 18: For example, if an otherwise conforming type-valid document incorrectly asserts that it is fully-tagged, the document is non-conforming. Had the assertion not been made, the document would have been conforming.
A system can offer means to make additional assertions.
Note 19: For example, as a parameter to the invocation of processing.
[199.1] added requirements = "SEEALSO", ps+, ("NONE"| (ps+, public identifier)+)
The public identifiers identify additional requirements for the document, including requirements unrelated to the SGML language. These requirements are in addition to, and must not contradict, the requirements of this International Standard. Failure to satisfy the added requirements is not a reportable markup error, except to the extent that such requirements are also expressed in other parameters of the SGML declaration.
Note 20: For example, this parameter could be used by an SGML system to signal the existence of requirements for specific entity constraint assertions, formatting conventions for specified element types, or data restrictions, such as that the number of cells in a table row does not exceed the number specified in some attribute. It is not a reportable markup error if the added required entity assertions are not present in the SGML declaration; if they are present, it is a reportable markup error if the the document fails to satisfy them, as that would have been the case even in the absence of the added requirements.
It is not an error if the system is unable to access an object named by the public identifiers.
Note 21: See Annex L "Added Requirements for XML" for an example.
 character reference = named character reference | numeric character reference | hex character reference [62.1] named character reference = cro, function name, reference end [62.2] numeric character reference = cro, character number, reference end [62.3] hex character reference = hcro, hexdigit+, reference end
A hexdigit is a digit or lowercase a-f or uppercase A-F. The length of the hex digit string cannot exceed NAMELEN.
Name String Number Mode Constraint Description HCRO (none) (none) CON LIT HEX Hex character reference open NESTC (NET) (none) TAG NET-enabling start-tag close NET / 47 CON ELEM Null end-tag
HEX constraint: must be followed by a hexdigit.
If no assignment is made to NESTC, the NET is used.
 net-enabling start-tag = stago, generic identifier specification, attribute specification list, s*, nestc
 attribute definition list declaration = mdo, "ATTLIST", ps+, ((associated element type | (rni, ("IMPLICIT"|"ALL")))| (rni, "NOTATION", ps+, (associated notation name | (rni, ("IMPLICIT"|"ALL"))))), ps+, attribute definition list, ps*, mdc where the keywords indicate the objects associated with the attributes: NOTATION indicates that the associated objects are notations. IMPLICIT means all the implicitly defined element types or notations. ALL means all element types or notations. [149.1] associated notation name = (notation name | name group)
IMPLICIT and ALL are the equivalent of name groups.
The same element type or notation may be the associated object in multiple ATTLIST declarations. An attempt to redefine an attribute that was previously defined for an associated object is not an error; the earliest definition prevails (just as for entity declarations). However, definitions associated with ALL can be overridden by subsequent attribute declarations for specific element types or notations, including definitions specified with IMPLICIT.
 attribute definition list = attribute definition?, (ps+, attribute definition)*
 declared value = "CDATA"|"ENTITY"|"ENTITIES"|"ID"|"IDREF"|"IDREFS"|"NAME"|"NAMES"| "NMTOKEN"|"NMTOKENS"|"NUMBER"|"NUMBERS"|"NUTOKEN"|"NUTOKENS"| notation|name token group|data specification [145.1] data specification = "DATA", ps+, notation name, data attribute specification?, where: "notation name" identifies the data content notation of the attribute's value "data attribute specification" specifies the corresponding data attributes
The value of an attribute whose declared value is "data specification" is character data.
 document type name = (generic identifier | (rni, "IMPLIED")) where: IMPLIED means the element type name of the document element.
It is a reportable markup error if IMPLIED is specified and the document instance does not begin with the start-tag of the document element.
IMPLIED cannot be specified if the explicit link or concur features are in use.
 owner identifier = ISO owner identifier | registered owner identifier | unregistered owner identifier | internet domain name owner identifier [83.1] internet domain name owner identifier = "+//IDN ", minimum data where the minimum data must begin with an internet domain name.
Note 22: The string "IDN domain.name" is treated as an ISO/IEC 9070 "registered owner prefix". Any sub-domain names could be expressed as owner name components. For example, the internet domain name in "http://www.someisp.net/users/mtb" could occur in an FPI as:
Note 23: When constructing a public text owner identifier using an internet domain name, users may wish to consider the name's potential lifespan and that of the objects to be identified by public identifiers that use it.
Semicolon, exclamation point, asterisk, number sign, commercial at sign, dollar sign, underscore, and percent sign are members of the abstract character class "special", which is usable in minimum data.
An element of a type declared EMPTY, or that is forced to be EMPTY by an explicit content reference attribute, cannot contain any text, including white space, other markup, or included subelements. Markup minimization can be applied to such elements (7.3).
A referenced parameter entity must consist of zero or more of the consecutive complete tokens that follow the ts in which the reference occurs in the same group (i.e., at the same nesting level), together with any intervening ts separators and connectors, and optionally with surrounding separators and connectors. The entity must end within the same group.
An Ee can occur in a ts only if the reference to the entity the Ee terminates occurs in the same group (i.e., at the same nesting level).
 entity set = (entity declaration | attribute definition list declaration | notation declaration | ds)* where: The keyword "NOTATION" must be specified in the attribute definition list declaration.
 SGML subdocument entity = (s*, SGML declaration)?, prolog, document instance set, Ee
If the SGML declaration is omitted, the subdocument uses the SGML declaration applicable to the entity from which the subdocument entity is referenced.
An SGML system has the option of offering the ability, at the user's request, to parse a fully-tagged document instance as though some or all of its associated document type declaration did not exist. Doing so has the same effect as implying the ignored definitions (see K.3.7).
Note 24: For example, the user might request, via an invocation parameter, that the external subset should be ignored.
If the entire document type declaration is to be ignored, the document type name is determined as though it had been specified as #IMPLIED, but no attempt is made to reference an external subset.
These additional requirements have the formal public identifier "ISO 8879//NOTATION Application Requirements for XML//EN".
This is version 1.0 of this annex.
Note: Pointers to revised versions of this annex, and other SGML-related information that may change over time, can be found at the International SGML User's Group web site at URL "http://www.sil.org/sgml/isgmlug/". The SGML Users' Group is an international non-profit membership organization, chartered as an educational charity in the United Kingdom, and is a liaison member of the ISO/IEC subcommittee that developed SGML. Nevertheless, the documents that it distributes have not been subject to ISO/IEC review procedures, have no official status, and are not endorsed by the ISO or IEC or any of its national member bodies or affiliates.
The Extensible Markup Language (XML) is the core subset of SGML functionality developed by the World Wide Web Consortium (W3C) for exchanging SGML documents over the World Wide Web. The current specification for XML can be found at the W3C web site at "http://www.w3.org/TR/".
The XML specification covers the following aspects of an SGML application and system:
XML distinguishes two classes of conforming documents:
A full-SGML validating parser cannot validate documents for conformance to XML unless it is specially modified to support XML. That is because some of XML's language restrictions cannot be expressed in the SGML declaration. Those restrictions can be found in http://www.w3.org/TR/NOTE-sgml-xml.
XML documents implicitly contain the following SGML declaration.
<!SGML -- SGML Declaration for XML -- "ISO 8879:1986 (WWW)" CHARSET BASESET "ISO Registration Number 176//CHARSET ISO/IEC 10646-1:1993 UCS-4 with implementation level 3//ESC 2/5 2/15 4/6" DESCSET 0 9 UNUSED 9 2 9 11 2 UNUSED 13 1 13 14 18 UNUSED 32 95 32 127 1 UNUSED 128 32 UNUSED 160 1113952 160 -- 160 + 1113952 = 0x110000 -- CAPACITY NONE SCOPE DOCUMENT SYNTAX SHUNCHAR NONE BASESET "ISO Registration Number 176//CHARSET ISO/IEC 10646-1:1993 UCS-4 with implementation level 3//ESC 2/5 2/15 4/6" DESCSET 0 1114112 0 FUNCTION RE 13 RS 10 SPACE 32 TAB SEPCHAR 9 NAMING LCNMSTRT "" UCNMSTRT "" NAMESTRT 95 170 181 186 192-214 216-246 248-305 305-383 383-452 452-455 455-458 458-497 497-501 506-535 592-680 688-696 699-705 736-740 768-837 864-865 890 902 904-906 908 910-929 914 920 922 928-929 931-939 934 940-974 976-982 986 988 990 992 994-1011 1025-1036 1038-1103 1105-1116 1118-1153 1155-1158 1168-1220 1223-1224 1227-1228 1232-1259 1262-1269 1272-1273 1329-1366 1369 1377-1415 1425-1441 1443-1465 1467-1469 1471 1473-1474 1476 1488-1514 1520-1522 1569-1594 1601-1618 1648-1719 1722-1726 1728-1742 1744-1747 1749-1768 1770-1773 2305-2307 2309-2361 2364-2381 2385-2388 2392-2403 2433-2435 2437-2444 2447-2448 2451-2472 2474-2480 2482 2486-2489 2492 2494-2500 2503-2504 2507-2509 2519 2524-2525 2527-2531 2544-2545 2562 2565-2570 2575-2576 2579-2600 2602-2608 2610-2611 2613-2614 2616-2617 2620 2622-2626 2631-2632 2635-2637 2649-2652 2654 2672-2676 2689-2691 2693-2699 2701 2703-2705 2707-2728 2730-2736 2738-2739 2741-2745 2748-2757 2759-2761 2763-2765 2784 2817-2819 2821-2828 2831-2832 2835-2856 2858-2864 2866-2867 2870-2873 2876-2883 2887-2888 2891-2893 2902-2903 2908-2909 2911-2913 2946-2947 2949-2954 2958-2960 2962-2965 2969-2970 2972 2974-2975 2979-2980 2984-2986 2990-2997 2999-3001 3006-3010 3014-3016 3018-3021 3031 3073-3075 3077-3084 3086-3088 3090-3112 3114-3123 3125-3129 3134-3140 3142-3144 3146-3149 3157-3158 3168-3169 3202-3203 3205-3212 3214-3216 3218-3240 3242-3251 3253-3257 3262-3268 3270-3272 3274-3277 3285-3286 3294 3296-3297 3330-3331 3333-3340 3342-3344 3346-3368 3370-3385 3390-3395 3398-3400 3402-3405 3415 3424-3425 3585-3630 3632-3642 3648-3653 3655-3662 3713-3714 3716 3719-3720 3722 3725 3732-3735 3737-3743 3745-3747 3749 3751 3754-3755 3757-3758 3760-3769 3771-3773 3776-3780 3784-3789 3804-3805 3864-3865 3893 3895 3897 3902-3911 3913-3945 3953-3972 3974-3979 3984-3989 3991 3993-4013 4017-4023 4025 4256-4293 4304-4342 4352-4441 4447-4514 4520-4601 7680-7835 7840-7929 7936-7957 7960-7965 7968-8005 8008-8013 8016-8023 8025 8027 8029 8031-8061 8064-8116 8118-8124 8126 8130-8132 8134-8140 8144-8147 8150-8155 8160-8172 8178-8180 8182-8188 8319 8400-8412 8417 8450 8455 8458-8467 8469 8472-8477 8484 8486 8488 8490-8497 8499-8504 8544-8578 12295 12321-12335 12353-12436 12441-12442 12449-12538 12549-12588 12593-12686 19968-40869 44032-55203 LCNMCHAR "" UCNMCHAR "" NAMECHAR 45 46 58 183 720 721 1600 1632-1641 1776-1785 2406-2415 2534-2543 2662-2671 2790-2799 2918-2927 3047-3055 3174-3183 3302-3311 3430-3439 3654 3664-3673 3782 3792-3801 3872-3881 8204-8207 8234-8238 8298-8303 12293 12337-12341 12443-12446 12540-12542 NAMECASE GENERAL NO ENTITY NO DELIM GENERAL SGMLREF HCRO "&#38;#x" -- 38 = ampersand -- NESTC "/" NET ">" PIC "?>" SHORTREF NONE NAMES SGMLREF QUANTITY NONE ENTITIES "amp" 38 "lt" 60 "gt" 62 "quot" 34 "apos" 39 FEATURES MINIMIZE DATATAG NO OMITTAG NO RANK NO SHORTTAG STARTTAG EMPTY NO UNCLOSED NO NETENABL IMMEDNET ENDTAG EMPTY NO UNCLOSED NO ATTRIB DEFAULT YES OMITNAME NO VALUE NO EMPTYNRM YES IMPLYDEF ELEMENT YES ENTITY YES NOTATION YES ATTLIST YES DOCTYPE YES LINK SIMPLE NO IMPLICIT NO EXPLICIT NO OTHER CONCUR NO SUBDOC NO FORMAL NO URN NO KEEPRSRE YES VALIDITY TAG ENTITIES REF ANY INTEGRAL YES APPINFO NONE SEEALSO "http://www.w3.org/TR/PR-xml-971208". >