<?xml version="1.0" encoding="UTF-8"?>
<grammar xmlns="http://relaxng.org/ns/structure/1.0" datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes">
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    <element name="doctype">
      <zeroOrMore>
        <ref name="decl"/>
      </zeroOrMore>
    </element>
  </start>
  <define name="decl">
    <choice>
      <ref name="elementDecl"/>
      <ref name="attlistDecl"/>
      <ref name="def"/>
      <ref name="overriddenDef"/>
      <ref name="externalIdRef"/>
      <ref name="includedSection"/>
      <ref name="ignoredSection"/>
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      <ref name="processingInstruction"/>
      <ref name="comment"/>
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      <ref name="enumGroupDef"/>
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      <ref name="nameSpec"/>
      <ref name="modelGroup"/>
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    <element name="modelGroup">
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      <ref name="modelGroup"/>
    </element>
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  <define name="datatypeDef">
    <element name="datatype">
      <ref name="name"/>
      <ref name="datatype"/>
    </element>
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  <define name="attributeDefaultDef">
    <element name="attributeDefault">
      <ref name="name"/>
      <ref name="attributeDefault"/>
    </element>
  </define>
  <define name="flagDef">
    <element name="flag">
      <ref name="name"/>
      <ref name="flag"/>
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  <define name="nameSpecDef">
    <element name="nameSpec">
      <ref name="name"/>
      <ref name="nameSpec"/>
    </element>
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  <define name="externalIdDef">
    <element name="externalId">
      <ref name="name"/>
      <ref name="externalId"/>
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  <define name="paramDef">
    <element name="param">
      <ref name="name"/>
      <text/>
    </element>
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        <ref name="def"/>
        <ref name="duplicateDef"/>
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  <define name="duplicateDef">
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      <ref name="name"/>
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  <define name="includedSection">
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        <attribute name="flag">
          <data type="NCName"/>
        </attribute>
      </optional>
      <zeroOrMore>
        <ref name="decl"/>
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      <optional>
        <attribute name="flag">
          <data type="NCName"/>
        </attribute>
      </optional>
      <text/>
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      <ref name="name"/>
      <zeroOrMore>
        <ref name="decl"/>
      </zeroOrMore>
    </element>
  </define>
  <define name="internalEntityDecl">
    <element name="internalEntity">
      <ref name="name"/>
      <text/>
    </element>
  </define>
  <define name="externalEntityDecl">
    <element name="externalEntity">
      <ref name="name"/>
      <ref name="externalId"/>
    </element>
  </define>
  <define name="notationDecl">
    <element name="notation">
      <ref name="name"/>
      <ref name="externalId"/>
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  <define name="processingInstruction">
    <element name="processingInstruction">
      <attribute name="target">
        <data type="NCName"/>
      </attribute>
      <text/>
    </element>
  </define>
  <define name="comment">
    <element name="comment">
      <text/>
    </element>
  </define>
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      <element name="tokenized">
        <choice>
          <attribute name="name">
            <choice>
              <value>NMTOKEN</value>
              <value>NMTOKENS</value>
              <value>ENTITY</value>
              <value>ENTITIES</value>
              <value>ID</value>
              <value>IDREF</value>
              <value>IDREFS</value>
            </choice>
          </attribute>
          <group>
            <optional>
              <attribute name="name">
                <value>NOTATION</value>
              </attribute>
            </optional>
            <ref name="enumGroup"/>
          </group>
        </choice>
      </element>
      <element name="cdata">
        <empty/>
      </element>
      <element name="datatypeRef">
        <ref name="name"/>
      </element>
    </choice>
  </define>
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    <zeroOrMore>
      <choice>
        <element name="enum">
          <data type="NMTOKEN"/>
        </element>
        <element name="enumGroupRef">
          <ref name="name"/>
        </element>
      </choice>
    </zeroOrMore>
  </define>
  <define name="enumGroupDef">
    <element name="enumGroup">
      <ref name="name"/>
      <ref name="enumGroup"/>
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  <define name="flag">
    <choice>
      <element name="include">
        <empty/>
      </element>
      <element name="ignore">
        <empty/>
      </element>
      <element name="flagRef">
        <ref name="name"/>
      </element>
    </choice>
  </define>
  <define name="attlistDecl">
    <element name="attlist">
      <ref name="nameSpec"/>
      <ref name="attributeGroup"/>
    </element>
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  <define name="attributeGroupDef">
    <element name="attributeGroup">
      <ref name="name"/>
      <ref name="attributeGroup"/>
    </element>
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    <zeroOrMore>
      <choice>
        <element name="attribute">
          <ref name="nameSpec"/>
          <ref name="datatype"/>
          <ref name="attributeDefault"/>
        </element>
        <element name="attributeGroupRef">
          <ref name="name"/>
        </element>
      </choice>
    </zeroOrMore>
  </define>
  <define name="attributeDefault">
    <choice>
      <element name="implied">
        <empty/>
      </element>
      <element name="required">
        <empty/>
      </element>
      <element>
        <choice>
          <name>default</name>
          <name>fixed</name>
        </choice>
        <text/>
      </element>
      <element name="attributeDefaultRef">
        <ref name="name"/>
      </element>
    </choice>
  </define>
  <define name="modelGroup">
    <choice>
      <element name="modelGroupRef">
        <ref name="name"/>
      </element>
      <element name="elementRef">
        <ref name="nameSpec"/>
      </element>
      <element name="oneOrMore">
        <ref name="modelGroup"/>
      </element>
      <element name="zeroOrMore">
        <ref name="modelGroup"/>
      </element>
      <element name="optional">
        <ref name="modelGroup"/>
      </element>
      <element name="pcdata">
        <empty/>
      </element>
      <element name="choice">
        <optional>
          <ref name="modelGroup"/>
          <oneOrMore>
            <ref name="modelGroup"/>
          </oneOrMore>
        </optional>
      </element>
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        <optional>
          <ref name="modelGroup"/>
          <oneOrMore>
            <ref name="modelGroup"/>
          </oneOrMore>
        </optional>
      </element>
    </choice>
  </define>
  <define name="externalId">
    <optional>
      <attribute name="system">
        <data type="anyURI"/>
      </attribute>
    </optional>
    <optional>
      <attribute name="public"/>
    </optional>
    <optional>
      <attribute name="xml:base">
        <data type="anyURI"/>
      </attribute>
    </optional>
  </define>
  <define name="name">
    <attribute name="name">
      <data type="NCName"/>
    </attribute>
  </define>
  <define name="nameSpec">
    <choice>
      <element name="name">
        <data type="Name"/>
      </element>
      <element name="nameSpecRef">
        <ref name="name"/>
      </element>
    </choice>
  </define>
</grammar>