<xs:schema targetNamespace="http://ltsc.ieee.org/xsd/LOM"
           xmlns="http://ltsc.ieee.org/xsd/LOM"
           xmlns:ag="http://ltsc.ieee.org/xsd/LOM/unique"
           xmlns:ex="http://ltsc.ieee.org/xsd/LOM/extend"
           xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           version="IEEE LTSC LOM XML 1.0">

  <xs:annotation>
    <xs:documentation>
       This work is licensed under the Creative Commons Attribution-ShareAlike
       License.  To view a copy of this license, see the file license.txt,
       visit http://creativecommons.org/licenses/by-sa/2.0 or send a letter to
       Creative Commons, 559 Nathan Abbott Way, Stanford, California 94305, USA.
    </xs:documentation>

    <xs:documentation>
       This component schema defintion defines global schema data type declarations
       for data elements defined in the LOMv1.0 base schema.  This component XSD
       defines the aggregation relationship among the LOM data elements.  These aggregation
       relationships enforce the LOMv1.0 base schema requirement that elements can only
       be present in a LOM XML instance as elements of the aggregate element to which they
       belong.

       Duplicate declarations are included as comments for completeness.  These declarations
       should remain commented out or they can be removed completely.
    </xs:documentation>
  </xs:annotation>

  <xs:import namespace="http://ltsc.ieee.org/xsd/LOM/unique" schemaLocation="../unique/strict.xsd"/>
  <xs:import namespace="http://ltsc.ieee.org/xsd/LOM/extend" schemaLocation="../extend/strict.xsd"/>

  <!-- Element type declarations -->

  <!-- Learning Object Metadata -->
  <xs:complexType name="lom">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="general"/>
      <xs:group ref="lifeCycle"/>
      <xs:group ref="metaMetadata"/>
      <xs:group ref="technical"/>
      <xs:group ref="educational"/>
      <xs:group ref="rights"/>
      <xs:group ref="relation"/>
      <xs:group ref="annotation"/>
      <xs:group ref="classification"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:lom"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 1 General -->
  <xs:complexType name="general">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="identifier"/>
      <xs:group ref="title"/>
      <xs:group ref="language"/>
      <xs:group ref="descriptionUnbounded"/>
      <xs:group ref="keyword"/>
      <xs:group ref="coverage"/>
      <xs:group ref="structure"/>
      <xs:group ref="aggregationLevel"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:general"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 1.1 Identifier -->
  <xs:complexType name="identifier">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="catalog"/>
      <xs:group ref="entry"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:identifier"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 1.1.1 Catalog -->
  <xs:complexType name="catalog">
    <xs:simpleContent>
      <xs:extension base="CharacterString">
        <xs:attributeGroup ref="ag:catalog"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType> 

  <!-- 1.1.2 Entry -->
  <xs:complexType name="entry">
    <xs:simpleContent>
      <xs:extension base="CharacterString">
        <xs:attributeGroup ref="ag:entry"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <!-- 1.2 Title -->
  <xs:complexType name="title">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:title"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>


  <!-- 1.3 Language -->
  <xs:complexType name="language">
    <xs:simpleContent>
      <xs:extension base="LanguageId">
        <xs:attributeGroup ref="ag:language"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <!-- 1.4 Description
  <xs:complexType name="description">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:description"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType> -->

  <!-- 1.5 Keyword -->
  <xs:complexType name="keyword">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:keyword"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 1.6 Coverage -->
  <xs:complexType name="coverage">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:coverage"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 1.7 Structure -->
  <xs:complexType name="structure">
    <xs:complexContent>
      <xs:extension base="structureVocab">
        <xs:attributeGroup ref="ag:structure"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 1.8 Aggregation Level -->
  <xs:complexType name="aggregationLevel">
    <xs:complexContent>
      <xs:extension base="aggregationLevelVocab">
        <xs:attributeGroup ref="ag:aggregationLevel"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 2 Life Cycle -->
  <xs:complexType name="lifeCycle">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="version"/>
      <xs:group ref="status"/>
      <xs:group ref="contribute"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:lifeCycle"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 2.1 Version -->
  <xs:complexType name="version">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:version"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 2.2 Status -->
  <xs:complexType name="status">
    <xs:complexContent>
      <xs:extension base="statusVocab">
        <xs:attributeGroup ref="ag:status"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 2.3 Contribute -->
  <xs:complexType name="contribute">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="role"/>
      <xs:group ref="entityUnbounded"/>
      <xs:group ref="date"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:contribute"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 2.3.1 Role -->
  <xs:complexType name="role">
    <xs:complexContent>
      <xs:extension base="roleVocab">
        <xs:attributeGroup ref="ag:role"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 2.3.2 Entity
  <xs:complexType name="entity">
    <xs:simpleContent>
      <xs:extension base="VCard">
        <xs:attributeGroup ref="ag:entity"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType> -->

  <!-- 2.3.3 Date -->
  <xs:complexType name="date">
    <xs:complexContent>
      <xs:extension base="DateTime">
        <xs:attributeGroup ref="ag:date"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 3 Meta-Metadata -->
  <xs:complexType name="metaMetadata">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="identifier"/>
      <xs:group ref="contributeMeta"/>
      <xs:group ref="metadataSchema"/>
      <xs:group ref="language"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:metaMetadata"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 3.1 Identifier
  <xs:complexType name="identifier">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="catalog"/>
      <xs:group ref="entry"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:identifier"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType> -->

  <!-- 3.1.1 Catalog
  <xs:complexType name="catalog">
    <xs:simpleContent>
      <xs:extension base="CharacterString">
        <xs:attributeGroup ref="ag:catalog"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType> -->

  <!-- 3.1.2 Entry
  <xs:complexType name="entry">
    <xs:simpleContent>
      <xs:extension base="CharacterString">
        <xs:attributeGroup ref="ag:entry"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType> -->

  <!-- 3.2 Contribute -->
  <xs:complexType name="contributeMeta">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="roleMeta"/>
      <xs:group ref="entityUnbounded"/>
      <xs:group ref="date"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:contribute"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 3.2.1 Role -->
  <xs:complexType name="roleMeta">
    <xs:complexContent>
      <xs:extension base="roleMetaVocab">
        <xs:attributeGroup ref="ag:role"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 3.2.2 Entity
  <xs:complexType name="entity">
    <xs:simpleContent>
      <xs:extension base="VCard">
        <xs:attributeGroup ref="ag:entity"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType> -->

  <!-- 3.2.3 Date
  <xs:complexType name="date">
    <xs:complexContent>
      <xs:extension base="DateTime">
        <xs:attributeGroup ref="ag:date"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType> -->

  <!-- 3.3 Metadata Schema -->
  <xs:complexType name="metadataSchema">
    <xs:simpleContent>
      <xs:extension base="CharacterString">
        <xs:attributeGroup ref="ag:metadataSchema"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <!-- 3.4 Language 
  <xs:complexType name="language">
    <xs:simpleContent>
      <xs:extension base="LanguageId">
        <xs:attributeGroup ref="ag:language"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>-->

  <!-- 4 Technical -->
  <xs:complexType name="technical">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="format"/>
      <xs:group ref="size"/>
      <xs:group ref="location"/>
      <xs:group ref="requirement"/>
      <xs:group ref="installationRemarks"/>
      <xs:group ref="otherPlatformRequirements"/>
      <xs:group ref="duration"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:technical"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 4.1 Format -->
  <xs:complexType name="format">
    <xs:simpleContent>
      <xs:extension base="MimeType">
        <xs:attributeGroup ref="ag:format"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <!-- 4.2 Size -->
  <xs:complexType name="size">
    <xs:simpleContent>
      <xs:extension base="Size">
        <xs:attributeGroup ref="ag:size"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <!-- 4.3 Location -->
  <xs:complexType name="location">
    <xs:simpleContent>
      <xs:extension base="CharacterString">
        <xs:attributeGroup ref="ag:location"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <!-- 4.4 Requirement -->
  <xs:complexType name="requirement">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="orComposite"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:requirement"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 4.4.1 OrComposite -->
  <xs:complexType name="orComposite">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="type"/>
      <xs:group ref="name"/>
      <xs:group ref="minimumVersion"/>
      <xs:group ref="maximumVersion"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:orComposite"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 4.4.1.1 Type -->
  <xs:complexType name="type">
    <xs:complexContent>
      <xs:extension base="typeVocab">
        <xs:attributeGroup ref="ag:type"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 4.4.1.2 Name -->
  <xs:complexType name="name">
    <xs:complexContent>
      <xs:extension base="nameVocab">
        <xs:attributeGroup ref="ag:name"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 4.4.1.3 Minimum Version -->
  <xs:complexType name="minimumVersion">
    <xs:simpleContent>
      <xs:extension base="CharacterString">
        <xs:attributeGroup ref="ag:minimumVersion"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <!-- 4.4.1.4 Maximum Version -->
  <xs:complexType name="maximumVersion">
    <xs:simpleContent>
      <xs:extension base="CharacterString">
        <xs:attributeGroup ref="ag:maximumVersion"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <!-- 4.5 Installation Remarks -->
  <xs:complexType name="installationRemarks">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:installationRemarks"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 4.6 Other Platform Requirements -->
  <xs:complexType name="otherPlatformRequirements">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:otherPlatformRequirements"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 4.7 Duration -->
  <xs:complexType name="duration">
    <xs:complexContent>
      <xs:extension base="Duration">
        <xs:attributeGroup ref="ag:duration"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 5 Educational -->
  <xs:complexType name="educational">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="interactivityType"/>
      <xs:group ref="learningResourceType"/>
      <xs:group ref="interactivityLevel"/>
      <xs:group ref="semanticDensity"/>
      <xs:group ref="intendedEndUserRole"/>
      <xs:group ref="context"/>
      <xs:group ref="typicalAgeRange"/>
      <xs:group ref="difficulty"/>
      <xs:group ref="typicalLearningTime"/>
      <xs:group ref="descriptionUnbounded"/>
      <xs:group ref="language"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:educational"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 5.1 Interactivity Type -->
  <xs:complexType name="interactivityType">
    <xs:complexContent>
      <xs:extension base="interactivityTypeVocab">
        <xs:attributeGroup ref="ag:interactivityType"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 5.2 Learning Resource Type -->
  <xs:complexType name="learningResourceType">
    <xs:complexContent>
      <xs:extension base="learningResourceTypeVocab">
        <xs:attributeGroup ref="ag:learningResourceType"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 5.3 Interactivity Level -->
  <xs:complexType name="interactivityLevel">
    <xs:complexContent>
      <xs:extension base="interactivityLevelVocab">
        <xs:attributeGroup ref="ag:interactivityLevel"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 5.4 Semantic Density -->
  <xs:complexType name="semanticDensity">
    <xs:complexContent>
      <xs:extension base="semanticDensityVocab">
        <xs:attributeGroup ref="ag:semanticDensity"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 5.5 Intended End User Role -->
  <xs:complexType name="intendedEndUserRole">
    <xs:complexContent>
      <xs:extension base="intendedEndUserRoleVocab">
        <xs:attributeGroup ref="ag:intendedEndUserRole"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 5.6 Context -->
  <xs:complexType name="context">
    <xs:complexContent>
      <xs:extension base="contextVocab">
        <xs:attributeGroup ref="ag:context"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 5.7 Typical Age Range -->
  <xs:complexType name="typicalAgeRange">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:typicalAgeRange"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 5.8 Difficulty -->
  <xs:complexType name="difficulty">
    <xs:complexContent>
      <xs:extension base="difficultyVocab">
        <xs:attributeGroup ref="ag:difficulty"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 5.9 Typical Learning Time -->
  <xs:complexType name="typicalLearningTime">
    <xs:complexContent>
      <xs:extension base="Duration">
        <xs:attributeGroup ref="ag:typicalLearningTime"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 5.10 Description
  <xs:complexType name="description">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:description"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType> -->

  <!-- 5.11 Language
  <xs:complexType name="language">
    <xs:simpleContent>
      <xs:extension base="LanguageId">
        <xs:attributeGroup ref="ag:language"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType> -->

  <!-- 6 Rights -->
  <xs:complexType name="rights">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="cost"/>
      <xs:group ref="copyrightAndOtherRestrictions"/>
      <xs:group ref="description"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:rights"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 6.1 Cost -->
  <xs:complexType name="cost">
    <xs:complexContent>
      <xs:extension base="costVocab">
        <xs:attributeGroup ref="ag:cost"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 6.2 Copyright and Other Restrictions -->
  <xs:complexType name="copyrightAndOtherRestrictions">
    <xs:complexContent>
      <xs:extension base="copyrightAndOtherRestrictionsVocab">
        <xs:attributeGroup ref="ag:copyrightAndOtherRestrictions"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 6.3 Description -->
  <xs:complexType name="description">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:description"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 7 Relation -->
  <xs:complexType name="relation">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="kind"/>
      <xs:group ref="resource"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:relation"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 7.1 Kind -->
  <xs:complexType name="kind">
    <xs:complexContent>
      <xs:extension base="kindVocab">
        <xs:attributeGroup ref="ag:kind"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 7.2 Resource -->
  <xs:complexType name="resource">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="identifier"/>
      <xs:group ref="description"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:resource"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 7.2.1 Identifier
  <xs:complexType name="identifier">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="catalog"/>
      <xs:group ref="entry"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:identifier"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType> -->

  <!-- 7.2.1.1 Catalog
  <xs:complexType name="catalog">
    <xs:simpleContent>
      <xs:extension base="CharacterString">
        <xs:attributeGroup ref="ag:catalog"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType> -->

  <!-- 7.2.1.2 Entry
  <xs:complexType name="entry">
    <xs:simpleContent>
      <xs:extension base="CharacterString">
        <xs:attributeGroup ref="ag:entry"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType> -->

  <!-- 7.2.2 Description
  <xs:complexType name="description">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:description"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType> -->

  <!-- 8 Annotation -->
  <xs:complexType name="annotation">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="entity"/>
      <xs:group ref="date"/>
      <xs:group ref="description"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:annotation"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 8.1 Entity -->
  <xs:complexType name="entity">
    <xs:simpleContent>
      <xs:extension base="VCard">
        <xs:attributeGroup ref="ag:entity"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <!-- 8.2 Date
  <xs:complexType name="date">
    <xs:complexContent>
      <xs:extension base="DateTime">
        <xs:attributeGroup ref="ag:date"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType> -->

  <!-- 8.3 Description
  <xs:complexType name="description">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:description"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType> -->

  <!-- 9 Classification -->
  <xs:complexType name="classification">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="purpose"/>
      <xs:group ref="taxonPath"/>
      <xs:group ref="description"/>
      <xs:group ref="keyword"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:classification"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 9.1 Purpose -->
  <xs:complexType name="purpose">
    <xs:complexContent>
      <xs:extension base="purposeVocab">
        <xs:attributeGroup ref="ag:purpose"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 9.2 Taxon Path -->
  <xs:complexType name="taxonPath">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="source"/>
      <xs:group ref="taxon"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:taxonPath"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 9.2.1 Source -->
  <xs:complexType name="source">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:source"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 9.2.2 Taxon -->
  <xs:complexType name="taxon">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="id"/>
      <xs:group ref="entryTaxon"/>
      <xs:group ref="ex:customElements"/>
    </xs:choice>
    <xs:attributeGroup ref="ag:taxon"/>
    <xs:attributeGroup ref="ex:customAttributes"/>
  </xs:complexType>

  <!-- 9.2.2.1 Id -->
  <xs:complexType name="id">
    <xs:simpleContent>
      <xs:extension base="CharacterString">
        <xs:attributeGroup ref="ag:id"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <!-- 9.2.2.2 Entry -->
  <xs:complexType name="entryTaxon">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:entry"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <!-- 9.3 Description
  <xs:complexType name="description">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:description"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType> -->

  <!-- 9.4 Keyword
  <xs:complexType name="keyword">
    <xs:complexContent>
      <xs:extension base="LanguageString">
        <xs:attributeGroup ref="ag:keyword"/>
        <xs:attributeGroup ref="ex:customAttributes"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType> -->

</xs:schema>