NOTE-sgml-xml-971215
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<!doctype html public '-//W3C//DTD HTML 4.0 Transitional//EN' 'http://www.w3.org/TR/REC-html40-971218/loose.dtd'>
<HTML><HEAD><meta name='GENERATOR' content='XML/XH/Lark'><TITLE>Comparison of SGML and XML</TITLE></HEAD><BODY BGCOLOR='#ffffff'>
<H3 align='right'><A HREF='http://www.w3.org/'><IMG align='left' alt='W3C' src='http://www.w3.org/Icons/WWW/w3c_home'></A>NOTE-sgml-xml-971215</H3><br><H1 align='center'>Comparison of SGML and XML</H1>
<h3 align='center'>World Wide Web Consortium Note
15-December-1997 </h3>
<BR>
<DL><DT>This version:</DT>
<dd><A HREF='http://www.w3.org/TR/NOTE-sgml-xml-971215'>http://www.w3.org/TR/NOTE-sgml-xml-971215</A></DL>
<dl><dt>Author:</dt>
<DD>
James Clark
<A HREF='mailto:jjc@jclark.com'><jjc@jclark.com></A>
</DD>
</dl>
<hr><h2>Status of this document</h2><p>
This document is a NOTE made available by the W3 Consortium for discussion only. This indicates no
endorsement of its content, nor that the Consortium has, is, or will be allocating any resources to the issues
addressed by the NOTE.<BR>
Errors or omissions in this document should be reported to the
<A HREF='mailto:jjc@jclark.com'>author</A>.<BR>
</p><hr>
<H2>Abstract</H2><P>
This document provides a detailed comparison of SGML (ISO 8879) and XML.<BR>
</P><HR>
<H1>Comparison of SGML and XML</H1><H1>Version 1.0</H1><h2>Table of Contents</h2>1. <A HREF='#null'>Differences Between XML and SGML</A><BR>
2. <A HREF='#null2'>Transforming SGML to XML</A><BR>
3. <A HREF='#null3'>SGML Declaration for XML</A><BR>
<HR>
<H2><A NAME='null'>1. Differences Between XML and SGML</a></h2>
<P>XML allows only documents that use the SGML declaration in this note. This
declares all the following SGML features as <code>NO</code>:</P>
<UL>
<LI><code>DATATAG</code></LI>
<LI><code>OMITTAG</code></LI>
<LI><code>RANK</code></LI>
<LI><code>LINK</code> (<code>SIMPLE</code>, <code>IMPLICIT</code> and
<code>EXPLICIT</code>)</LI>
<LI><code>CONCUR</code></LI>
<LI><code>SUBDOC</code></LI>
<LI><code>FORMAL</code></LI>
</UL>
<P>Note that it differs from the reference concrete syntax in a number of
ways:</P>
<UL>
<LI>It also declares no short reference delimiters; it follows that <code>
SHORTREF</code> and <code>USEMAP</code> declarations cannot occur in XML</LI>
<LI>The <code>PIC</code> (processing instruction close) delimiter is
<CODE><FONT SIZE='+1'>?></FONT></CODE></LI>
<LI>Quantities and capacities are effectively unlimited</LI>
<LI>Names are case sensitive (<code>NAMECASE GENERAL</code> is
<code>NO</code>)</LI>
<LI>Underscore and colon are allowed in names</LI>
<LI>Names can use Unicode characters and are not restricted to ASCII
</LI>
</UL>
<P>The following constructs which are permitted in SGML when <code>SHORTTAG
</code> is <code>YES</code> are not allowed in XML:</P>
<UL>
<LI>Unclosed start-tags</LI>
<LI>Unclosed end-tags</LI>
<LI>Empty start-tags</LI>
<LI>Empty end-tags</LI>
<LI>Attribute values in attribute specifications entered directly rather
than as literals</LI>
<LI>Attribute specifications that omit the attribute name</LI>
</UL>
<P><code>NET</code> delimiters can be used only to close an empty element. In
SGML without the Web SGML Adaptations Annex, the <code>NET</code> delimiter is declared as
<CODE><FONT SIZE='+1'>/></FONT></CODE>. With this approach, XML is not allowing null end-tags and is allowing
net-enabling start-tags only for elements with no end-tag. In SGML with the
Web SGML Adaptations Annex, there is a separate NESTC (net-enabling start tag close) delimiter.
This allows the XML <CODE><FONT SIZE='+1'><e/></FONT></CODE> syntax to be handled as a combination
of a net-enabling start-tag <CODE><FONT SIZE='+1'><e/</FONT></CODE> and a null end-tag
<CODE><FONT SIZE='+1'>></FONT></CODE>. With this approach, XML is allowing a net-enabling start-tag
only when immediately followed by a null end-tag.</P>
<P>XML imposes the following restrictions not in SGML:</P>
<UL>
<LI>Entity references
<UL>
<LI>Entity references must be closed with a <code>REFC</code> delimiter
</LI>
<LI>References to external data entities in content are not allowed
</LI>
<LI>General entity references in content are required to be synchronous
</LI>
<LI>External entity references in attribute values are not allowed</LI>
<LI>Parameter entity references are allowed in the internal subset only
within a declaration separator (that is, at a point where a markup declaration
could occur)</LI>
</UL>
</LI>
<LI>Character references
<UL>
<LI>Character references must be closed with a <code>REFC</code> delimiter
</LI>
<LI>Named character references are not allowed</LI>
<LI>Numeric character references to non-SGML characters are not allowed</LI>
</UL>
</LI>
<LI>Entity declarations
<UL>
<LI>A <code>#DEFAULT</code> entity cannot be declared</LI>
<LI>External <code>SDATA</code> entities are not allowed</LI>
<LI>External <code>CDATA</code> entities are not allowed</LI>
<LI>Internal <code>SDATA</code> entities are not allowed</LI>
<LI>Internal <code>CDATA</code> entities are not allowed</LI>
<LI><code>PI</code> entities are not allowed</LI>
<LI>Bracketed text entities are not allowed</LI>
<LI>External identifiers must include a system identifier</LI>
<LI>Attributes cannot be specified for an entity</LI>
<LI>The replacement text of general text entities and external parameter
entities is required to be well-formed</LI>
<LI>An ampersand in a parameter literal must be followed by
a syntactically valid entity reference or numeric character
reference</LI>
</UL>
</LI>
<LI>Attribute definition list declarations
<UL>
<LI>Associated element type in attribute definition list declarations
cannot be a name group</LI>
<LI>Attributes cannot be declared for a notation</LI>
<LI><code>CURRENT</code> attributes are not allowed</LI>
<LI>Content reference attributes are not allowed</LI>
<LI><code>NUTOKEN(S)</code> declared values are not allowed</LI>
<LI><code>NUMBER(S)</code> declared values are not allowed</LI>
<LI><code>NAME(S)</code> declared values are not allowed</LI>
<LI>A name token group must use the or connector</LI>
<LI>Attribute values specified as defaults in attribute definition list
declarations must be literals (SGML allows them not to be even when
<code>SHORTTAG</code> is <code>NO</code>)</LI>
</UL>
</LI>
<LI>Element type declarations
<UL>
<LI>Associated element type in element type declaration cannot be a name
group</LI>
<LI>In an element declaration, a generic identifier cannot be specified
as a rank stem and rank suffix (SGML allows this even when the <code>RANK</code>
feature is <code>NO</code>)</LI>
<LI>Minimization parameters in element declarations are not
allowed</LI>
<LI><code>RCDATA</code> declared content are not allowed</LI>
<LI><code>CDATA</code> declared content are not allowed</LI>
<LI>Content models cannot use the and connector</LI>
<LI>Content models for mixed content have a restricted form</LI>
<LI>Inclusions are not allowed</LI>
<LI>Exclusions are not allowed</LI>
</UL>
</LI>
<LI>Comments
<UL>
<LI>A parameter separator cannot contain comments; this means that markup
declarations (other than comment declarations) cannot contain comments
</LI>
<LI>Empty comment declarations (<CODE><FONT SIZE='+1'><!></FONT></CODE> in the reference
concrete syntax) are not allowed</LI>
<LI>A comment declaration cannot contain more than one comment</LI>
<LI>In a comment declaration, an S separator is not allowed before the
final <code>MDC</code></LI>
</UL>
</LI>
<LI>Processing instructions
<UL>
<LI>Processing instructions must start with a name (the PI target)
</LI>
<LI>A processing instruction whose PI target is <CODE><FONT SIZE='+1'>xml</FONT></CODE> can
only occur at the beginning of a external entity and must be an XML declaration
if it occurs in the document entity, and otherwise an text declaration</LI>
<LI>A PI target must not match <CODE><FONT SIZE='+1'>[Xx][Mm][Ll]</FONT></CODE> unless it is
<CODE><FONT SIZE='+1'>xml</FONT></CODE></LI>
</UL>
</LI>
<LI>Marked sections
<UL>
<LI>In marked section declarations, <code>TEMP</code> status keyword is not
allowed</LI>
<LI><code>RCDATA</code> marked sections are not allowed</LI>
<LI><code>INCLUDE</code>/<code>IGNORE</code> marked sections are not allowed
in the document instance</LI>
<LI>In a marked section declaration, a status keyword specification that
contains no status keywords is not allowed</LI>
<LI>In a marked section declaration, a status keyword specification cannot
contain more than one status keyword</LI>
<LI>Marked sections are not allowed in the internal subset</LI>
<LI>Parameter separators are not allowed in status keyword specifications
in the document instance; in particular, parameter entity references are not
allowed</LI>
</UL>
</LI>
<LI>Other
<UL>
<LI>Names beginning with <CODE><FONT SIZE='+1'>[Xx][Mm][Ll]</FONT></CODE> are reserved</LI>
<LI>The SGML declaration must be implied and cannot be explicitly present
in the document entity</LI>
<LI>When <CODE><FONT SIZE='+1'><</FONT></CODE> and <CODE><FONT SIZE='+1'>&</FONT></CODE> occur as data, they
must be entered as <CODE><FONT SIZE='+1'>&lt;</FONT></CODE> and <CODE><FONT SIZE='+1'>&amp;</FONT></CODE></LI>
<LI>A parameter separator required by the formal syntax must always
be present and cannot be omitted when it is adjacent to a delimiter</LI>
</UL>
</LI>
</UL>
<P>XML predefines the semantics of the attributes <CODE><FONT SIZE='+1'>xml:space</FONT></CODE> and
<CODE><FONT SIZE='+1'>xml:lang</FONT></CODE>. It also reserves all attribute, element type and
notation names beginning with <CODE><FONT SIZE='+1'>[Xx][Mm][Ll]</FONT></CODE>.</P>
<P>XML requires that an SGML parser use an entity manager that behaves as
follows:</P>
<UL>
<LI>Lines are terminated by newline (Unicode code #X000A) rather than
being delimited by RS and RE as with a typical SGML entity manager</LI>
<LI>System identifiers are treated as URLs</LI>
<LI>The entity manager must support entities encoded in UTF-16 and UTF-8,
and must be able automatically to detect which encoding an entity uses based on
the presence of the byte order mark</LI>
<LI>The entity manager should be able to recognize the encoding declaration
in the XML declaration and encoding PI and use it to determine the encoding
of entity</LI>
</UL>
<P>XML imposes requirements on the information that a parser must make
available to an application.</P>
<P>XML depends on the following changes to SGML made by Web SGML Adaptations Annex:
</P>
<UL>
<LI><code>HCRO</code> delimiter (for hex numeric character references);
for XML this is <CODE><FONT SIZE='+1'>&#x</FONT></CODE></LI>
<LI>EMPTYNRM feature that allows elements declared <code>EMPTY</code> to have
end-tags</LI>
<LI><code>NESTC</code> delimiter</LI>
<LI>Duplicate enumerated attribute tokens are allowed</LI>
<LI>Relaxation of rules on use of parameter entity references inside
groups</LI>
<LI>Multiple <code>ATTLIST</code> declarations for a single element type
</LI>
<LI><code>ATTLIST</code> declarations which don't declare any attributes
</LI>
<LI>KEEPRSRE feature that turns off SGML's rules for ignoring RSs and REs</LI>
<LI>Fully-tagged SGML documents; a document that is fully-tagged
but not type-valid is a conforming SGML document; this makes all XML
documents, including those that are well-formed but not valid,
conforming SGML documents</LI>
<LI>Predefined data character entities in the SGML declaration (for lt,
amp and so on)</LI>
<LI>Unlimited capacities and quantities</LI>
</UL>
<P>The Web SGML Adaptations Annex also enables some XML restrictions
to be enforced in SGML:</P>
<UL>
<LI><code>SHORTTAG</code> is unbundled, so the SGML declaration can allow
attribute defaulting and <code>NET</code> without allowing other
<code>SHORTTAG</code> constructs</LI>
<LI>The SGML declaration can assert that a document is integrally stored,
which disallows improperly nested entity references in content</LI>
</UL>
<H2><A NAME='null2'>2. Transforming SGML to XML</a></h2>
<P>For most restrictions in XML that go beyond SGML,
it is possible to transform
an SGML document automatically into a document that meets the restrictions,
and is equivalent in the sense that it has the same ESIS. There are a number
of restrictions for which this is not the case:</P>
<DL>
<DT>External <code>SDATA</code> entities, external <code>CDATA</code> entities
</DT>
<DD>
These could be transformed into <code>NDATA</code> entities.
</DD>
<DT>Subdocument entities</DT>
<DD>
These could be converted into <code>NDATA</code> entities with a notation that
indicates that they are SGML or XML.
</DD>
<DT>References to external data entities in content</DT>
<DD>
These could be transformed into an empty element with an attribute whose
declared value is <code>ENTITY</code>.
</DD>
<DT>Data attributes</DT>
<DD>
Since an external data entity can only be used in an <code>ENTITY</code> or
<code>ENTITIES</code> attribute on an element, these could be transformed into
other attributes on the element.
</DD>
<DT>Internal <code>SDATA</code> entities</DT>
<DD>
References could be transformed into numeric character references to the
appropriate Unicode character; if used in an entity or entities attribute,
the entity will have to be made external.
</DD>
<DT>Internal <code>CDATA</code> entities</DT>
<DD>
If used in an <code>ENTITY</code> or <code>ENTITIES</code> attribute, the entity
will have to be made external (references to <code>CDATA</code> entities are
not part of ESIS).
</DD>
<DT><code>PI</code> entities</DT>
<DD>
If they contain <CODE><FONT SIZE='+1'>?></FONT></CODE>, they cannot be converted into an XML PI.
It could be an application convention that entity references are replaced
in PIs. Also if they do not start with a name, they cannot be converted into
a well-formed XML PI.
</DD>
<DT>names</DT>
<DD>
An SGML document can have a concrete syntax which allows characters in
names that XML does not allow in names.
</DD>
</DL>
<H2><A NAME='null3'>3. SGML Declaration for XML</a></h2>
<P>The following SGML declaration takes advantage of
the Extended Naming Rules Technical Corrigendum to ISO 8879,
but does not make use of the Web SGML Adaptations Annex:</P>
<table cellpadding='5' border='1' bgcolor='#80ffff' width='100%'><tr><td><code><font size='+1'><!SGML -- SGML Declaration for XML --<BR> "ISO 8879:1986 (ENR)"<BR><BR> CHARSET<BR> BASESET<BR> "ISO Registration Number 176//CHARSET<BR> ISO/IEC 10646-1:1993 UCS-4 with implementation <BR> level 3//ESC 2/5 2/15 4/6"<BR> DESCSET<BR> 0 9 UNUSED<BR> 9 2 9<BR> 11 2 UNUSED<BR> 13 1 13<BR> 14 18 UNUSED<BR> 32 95 32<BR> 127 1 UNUSED<BR> 128 32 UNUSED<BR> 160 55136 160<BR> 55296 2048 UNUSED -- surrogates --<BR> 57344 8190 57344<BR> 65534 2 UNUSED -- FFFE and FFFF --<BR> 65536 1048576 65536<BR> CAPACITY SGMLREF<BR> -- Capacities are not restricted in XML --<BR> TOTALCAP 99999999<BR> ENTCAP 99999999<BR> ENTCHCAP 99999999<BR> ELEMCAP 99999999<BR> GRPCAP 99999999<BR> EXGRPCAP 99999999<BR> EXNMCAP 99999999<BR> ATTCAP 99999999<BR> ATTCHCAP 99999999<BR> AVGRPCAP 99999999<BR> NOTCAP 99999999<BR> NOTCHCAP 99999999<BR> IDCAP 99999999<BR> IDREFCAP 99999999<BR> MAPCAP 99999999<BR> LKSETCAP 99999999<BR> LKNMCAP 99999999<BR><BR><BR> SCOPE DOCUMENT<BR><BR> SYNTAX<BR> SHUNCHAR NONE<BR> BASESET "ISO Registration Number 176//CHARSET<BR> ISO/IEC 10646-1:1993 UCS-4 with implementation <BR> level 3//ESC 2/5 2/15 4/6"<BR> DESCSET<BR> 0 1114112 0<BR> FUNCTION<BR> RE 13<BR> RS 10<BR> SPACE 32<BR> TAB SEPCHAR 9<BR><BR> NAMING<BR> LCNMSTRT ""<BR> UCNMSTRT ""<BR> NAMESTRT<BR> 58 95 192-214 216-246 248-305 308-318 321-328<BR> 330-382 384-451 461-496 500-501 506-535 592-680<BR> 699-705 902 904-906 908 910-929 931-974 976-982<BR> 986 988 990 992 994-1011 1025-1036 1038-1103<BR> 1105-1116 1118-1153 1168-1220 1223-1224<BR> 1227-1228 1232-1259 1262-1269 1272-1273<BR> 1329-1366 1369 1377-1414 1488-1514 1520-1522<BR> 1569-1594 1601-1610 1649-1719 1722-1726<BR> 1728-1742 1744-1747 1749 1765-1766 2309-2361<BR> 2365 2392-2401 2437-2444 2447-2448 2451-2472<BR> 2474-2480 2482 2486-2489 2524-2525 2527-2529<BR> 2544-2545 2565-2570 2575-2576 2579-2600<BR> 2602-2608 2610-2611 2613-2614 2616-2617<BR> 2649-2652 2654 2674-2676 2693-2699 2701<BR> 2703-2705 2707-2728 2730-2736 2738-2739<BR> 2741-2745 2749 2784 2821-2828 2831-2832<BR> 2835-2856 2858-2864 2866-2867 2870-2873 2877<BR> 2908-2909 2911-2913 2949-2954 2958-2960<BR> 2962-2965 2969-2970 2972 2974-2975 2979-2980<BR> 2984-2986 2990-2997 2999-3001 3077-3084<BR> 3086-3088 3090-3112 3114-3123 3125-3129<BR> 3168-3169 3205-3212 3214-3216 3218-3240<BR> 3242-3251 3253-3257 3294 3296-3297 3333-3340<BR> 3342-3344 3346-3368 3370-3385 3424-3425<BR> 3585-3630 3632 3634-3635 3648-3653 3713-3714<BR> 3716 3719-3720 3722 3725 3732-3735 3737-3743<BR> 3745-3747 3749 3751 3754-3755 3757-3758 3760<BR> 3762-3763 3773 3776-3780 3904-3911 3913-3945<BR> 4256-4293 4304-4342 4352 4354-4355 4357-4359<BR> 4361 4363-4364 4366-4370 4412 4414 4416 4428<BR> 4430 4432 4436-4437 4441 4447-4449 4451 4453<BR> 4455 4457 4461-4462 4466-4467 4469 4510 4520<BR> 4523 4526-4527 4535-4536 4538 4540-4546 4587<BR> 4592 4601 7680-7835 7840-7929 7936-7957<BR> 7960-7965 7968-8005 8008-8013 8016-8023 8025<BR> 8027 8029 8031-8061 8064-8116 8118-8124 8126<BR> 8130-8132 8134-8140 8144-8147 8150-8155<BR> 8160-8172 8178-8180 8182-8188 8486 8490-8491<BR> 8494 8576-8578 12295 12321-12329 12353-12436<BR> 12449-12538 12549-12588 19968-40869 44032-55203<BR><BR> LCNMCHAR ""<BR> UCNMCHAR ""<BR> NAMECHAR<BR> 45-46 183 720-721 768-837 864-865 903 1155-1158<BR> 1425-1441 1443-1465 1467-1469 1471 1473-1474<BR> 1476 1600 1611-1618 1632-1641 1648 1750-1764<BR> 1767-1768 1770-1773 1776-1785 2305-2307 2364<BR> 2366-2381 2385-2388 2402-2403 2406-2415<BR> 2433-2435 2492 2494-2500 2503-2504 2507-2509<BR> 2519 2530-2531 2534-2543 2562 2620 2622-2626<BR> 2631-2632 2635-2637 2662-2673 2689-2691 2748<BR> 2750-2757 2759-2761 2763-2765 2790-2799<BR> 2817-2819 2876 2878-2883 2887-2888 2891-2893<BR> 2902-2903 2918-2927 2946-2947 3006-3010<BR> 3014-3016 3018-3021 3031 3047-3055 3073-3075<BR> 3134-3140 3142-3144 3146-3149 3157-3158<BR> 3174-3183 3202-3203 3262-3268 3270-3272<BR> 3274-3277 3285-3286 3302-3311 3330-3331<BR> 3390-3395 3398-3400 3402-3405 3415 3430-3439<BR> 3633 3636-3642 3654-3662 3664-3673 3761<BR> 3764-3769 3771-3772 3782 3784-3789 3792-3801<BR> 3864-3865 3872-3881 3893 3895 3897 3902-3903<BR> 3953-3972 3974-3979 3984-3989 3991 3993-4013<BR> 4017-4023 4025 8400-8412 8417 12293 12330-12335<BR> 12337-12341 12441-12442 12445-12446 12540-12542<BR><BR> NAMECASE<BR> GENERAL NO<BR> ENTITY NO<BR><BR><BR> DELIM<BR> GENERAL SGMLREF<BR> NET "/>"<BR> PIC "?>"<BR> SHORTREF NONE<BR> NAMES<BR> SGMLREF<BR><BR><BR> QUANTITY SGMLREF<BR> -- Quantities are not restricted in XML --<BR> ATTCNT 99999999<BR> ATTSPLEN 99999999<BR> -- BSEQLEN not used --<BR> -- DTAGLEN not used --<BR> -- DTEMPLEN not used --<BR> ENTLVL 99999999<BR> GRPCNT 99999999<BR> GRPGTCNT 99999999<BR> GRPLVL 99999999<BR> LITLEN 99999999<BR> NAMELEN 99999999<BR> -- no need to change NORMSEP --<BR> PILEN 99999999<BR> TAGLEN 99999999<BR> TAGLVL 99999999<BR><BR><BR> FEATURES<BR> MINIMIZE<BR> DATATAG NO<BR> OMITTAG NO<BR> RANK NO<BR> SHORTTAG YES -- SHORTTAG is needed for NET --<BR> LINK<BR> SIMPLE NO<BR> IMPLICIT NO<BR> EXPLICIT NO<BR> OTHER<BR> CONCUR NO<BR> SUBDOC NO<BR> FORMAL NO<BR> APPINFO NONE<BR>></font></code></td></tr></table>
<P>The following SGML declaration takes advantage of
the Web SGML Adaptations Annex to ISO 8879:</P>
<table cellpadding='5' border='1' bgcolor='#80ffff' width='100%'><tr><td><code><font size='+1'><!SGML -- SGML Declaration for XML --<BR> "ISO 8879:1986 (WWW)"<BR><BR> CHARSET<BR> BASESET<BR> "ISO Registration Number 176//CHARSET<BR> ISO/IEC 10646-1:1993 UCS-4 with implementation <BR> level 3//ESC 2/5 2/15 4/6"<BR> DESCSET<BR> 0 9 UNUSED<BR> 9 2 9<BR> 11 2 UNUSED<BR> 13 1 13<BR> 14 18 UNUSED<BR> 32 95 32<BR> 127 1 UNUSED<BR> 128 32 UNUSED<BR> 160 55136 160<BR> 55296 2048 UNUSED -- surrogates --<BR> 57344 8190 57344<BR> 65534 2 UNUSED -- FFFE and FFFF --<BR> 65536 1048576 65536<BR> CAPACITY NONE<BR><BR> SCOPE DOCUMENT<BR><BR> SYNTAX<BR> SHUNCHAR NONE<BR> BASESET "ISO Registration Number 176//CHARSET<BR> ISO/IEC 10646-1:1993 UCS-4 with implementation <BR> level 3//ESC 2/5 2/15 4/6"<BR> DESCSET<BR> 0 1114112 0<BR> FUNCTION<BR> RE 13<BR> RS 10<BR> SPACE 32<BR> TAB SEPCHAR 9<BR><BR> NAMING<BR> LCNMSTRT ""<BR> UCNMSTRT ""<BR> NAMESTRT<BR> 58 95 192-214 216-246 248-305 308-318 321-328<BR> 330-382 384-451 461-496 500-501 506-535 592-680<BR> 699-705 902 904-906 908 910-929 931-974 976-982<BR> 986 988 990 992 994-1011 1025-1036 1038-1103<BR> 1105-1116 1118-1153 1168-1220 1223-1224<BR> 1227-1228 1232-1259 1262-1269 1272-1273<BR> 1329-1366 1369 1377-1414 1488-1514 1520-1522<BR> 1569-1594 1601-1610 1649-1719 1722-1726<BR> 1728-1742 1744-1747 1749 1765-1766 2309-2361<BR> 2365 2392-2401 2437-2444 2447-2448 2451-2472<BR> 2474-2480 2482 2486-2489 2524-2525 2527-2529<BR> 2544-2545 2565-2570 2575-2576 2579-2600<BR> 2602-2608 2610-2611 2613-2614 2616-2617<BR> 2649-2652 2654 2674-2676 2693-2699 2701<BR> 2703-2705 2707-2728 2730-2736 2738-2739<BR> 2741-2745 2749 2784 2821-2828 2831-2832<BR> 2835-2856 2858-2864 2866-2867 2870-2873 2877<BR> 2908-2909 2911-2913 2949-2954 2958-2960<BR> 2962-2965 2969-2970 2972 2974-2975 2979-2980<BR> 2984-2986 2990-2997 2999-3001 3077-3084<BR> 3086-3088 3090-3112 3114-3123 3125-3129<BR> 3168-3169 3205-3212 3214-3216 3218-3240<BR> 3242-3251 3253-3257 3294 3296-3297 3333-3340<BR> 3342-3344 3346-3368 3370-3385 3424-3425<BR> 3585-3630 3632 3634-3635 3648-3653 3713-3714<BR> 3716 3719-3720 3722 3725 3732-3735 3737-3743<BR> 3745-3747 3749 3751 3754-3755 3757-3758 3760<BR> 3762-3763 3773 3776-3780 3904-3911 3913-3945<BR> 4256-4293 4304-4342 4352 4354-4355 4357-4359<BR> 4361 4363-4364 4366-4370 4412 4414 4416 4428<BR> 4430 4432 4436-4437 4441 4447-4449 4451 4453<BR> 4455 4457 4461-4462 4466-4467 4469 4510 4520<BR> 4523 4526-4527 4535-4536 4538 4540-4546 4587<BR> 4592 4601 7680-7835 7840-7929 7936-7957<BR> 7960-7965 7968-8005 8008-8013 8016-8023 8025<BR> 8027 8029 8031-8061 8064-8116 8118-8124 8126<BR> 8130-8132 8134-8140 8144-8147 8150-8155<BR> 8160-8172 8178-8180 8182-8188 8486 8490-8491<BR> 8494 8576-8578 12295 12321-12329 12353-12436<BR> 12449-12538 12549-12588 19968-40869 44032-55203<BR><BR> LCNMCHAR ""<BR> UCNMCHAR ""<BR> NAMECHAR<BR> 45-46 183 720-721 768-837 864-865 903 1155-1158<BR> 1425-1441 1443-1465 1467-1469 1471 1473-1474<BR> 1476 1600 1611-1618 1632-1641 1648 1750-1764<BR> 1767-1768 1770-1773 1776-1785 2305-2307 2364<BR> 2366-2381 2385-2388 2402-2403 2406-2415<BR> 2433-2435 2492 2494-2500 2503-2504 2507-2509<BR> 2519 2530-2531 2534-2543 2562 2620 2622-2626<BR> 2631-2632 2635-2637 2662-2673 2689-2691 2748<BR> 2750-2757 2759-2761 2763-2765 2790-2799<BR> 2817-2819 2876 2878-2883 2887-2888 2891-2893<BR> 2902-2903 2918-2927 2946-2947 3006-3010<BR> 3014-3016 3018-3021 3031 3047-3055 3073-3075<BR> 3134-3140 3142-3144 3146-3149 3157-3158<BR> 3174-3183 3202-3203 3262-3268 3270-3272<BR> 3274-3277 3285-3286 3302-3311 3330-3331<BR> 3390-3395 3398-3400 3402-3405 3415 3430-3439<BR> 3633 3636-3642 3654-3662 3664-3673 3761<BR> 3764-3769 3771-3772 3782 3784-3789 3792-3801<BR> 3864-3865 3872-3881 3893 3895 3897 3902-3903<BR> 3953-3972 3974-3979 3984-3989 3991 3993-4013<BR> 4017-4023 4025 8400-8412 8417 12293 12330-12335<BR> 12337-12341 12441-12442 12445-12446 12540-12542<BR><BR> NAMECASE<BR> GENERAL NO<BR> ENTITY NO<BR><BR> DELIM<BR> GENERAL SGMLREF<BR> HCRO "&#38;#x" -- 38 is the number for ampersand --<BR> NESTC "/"<BR> NET ">"<BR> PIC "?>"<BR> SHORTREF NONE<BR><BR> NAMES<BR> SGMLREF<BR><BR> QUANTITY NONE<BR><BR> ENTITIES<BR> "amp" 38<BR> "lt" 60<BR> "gt" 62<BR> "quot" 34<BR> "apos" 39<BR><BR> FEATURES<BR> MINIMIZE<BR> DATATAG NO<BR> OMITTAG NO<BR> RANK NO<BR> SHORTTAG<BR> STARTTAG<BR> EMPTY NO<BR> UNCLOSED NO <BR> NETENABL IMMEDNET<BR> ENDTAG<BR> EMPTY NO <BR> UNCLOSED NO<BR> ATTRIB<BR> DEFAULT YES<BR> OMITNAME NO<BR> VALUE NO<BR> EMPTYNRM YES<BR> IMPLYDEF<BR> ATTLIST YES<BR> DOCTYPE YES<BR> ELEMENT YES<BR> ENTITY YES<BR> NOTATION YES<BR> LINK<BR> SIMPLE NO<BR> IMPLICIT NO<BR> EXPLICIT NO<BR> OTHER<BR> CONCUR NO<BR> SUBDOC NO<BR> FORMAL NO<BR> URN NO<BR> KEEPRSRE YES<BR> VALIDITY TAG<BR> ENTITIES<BR> REF ANY<BR> INTEGRAL YES<BR> APPINFO NONE<BR> SEEALSO "ISO 8879//NOTATION Application Requirements for XML//EN"<BR>></font></code></td></tr></table>
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