<schema targetNamespace=“www.openarchives.org/OAI/2.0/”

      xmlns="http://www.w3.org/2001/XMLSchema"
      xmlns:oai="http://www.openarchives.org/OAI/2.0/"
      elementFormDefault="qualified"
      attributeFormDefault="unqualified">

<annotation>
  <documentation>
  XML Schema which can be used to validate replies to all OAI-PMH 
  v2.0 requests. Herbert Van de Sompel, 2002-05-13.
  Validated with XML Spy v.4.3 on 2002-05-13.
  Validated with XSV 1.203.2.45/1.106.2.22 on 2002-05-13.
  Added definition of protocolVersionType instead of using anonymous 
  type. No change of function. Simeon Warner, 2004-03-29.
  Tightened definition of UTCdatetimeType to enforce the restriction 
  to UTC Z notation. Simeon Warner, 2004-09-14.
  Corrected pattern matches for setSpecType and metadataPrefixType
  to agree with protocol specification. Simeon Warner, 2004-10-12.
  Spelling correction. Simeon Warner, 2008-12-07.
  $Date: 2004/10/12 15:20:29 $
  </documentation>
</annotation>

<element name="OAI-PMH" type="oai:OAI-PMHtype"/>

<complexType name="OAI-PMHtype">
  <sequence>
    <element name="responseDate" type="dateTime"/>
    <element name="request" type="oai:requestType"/>
    <choice>
      <element name="error" type="oai:OAI-PMHerrorType" maxOccurs="unbounded"/>
      <element name="Identify" type="oai:IdentifyType"/>
      <element name="ListMetadataFormats" type="oai:ListMetadataFormatsType"/>
      <element name="ListSets" type="oai:ListSetsType"/>
      <element name="GetRecord" type="oai:GetRecordType"/>
      <element name="ListIdentifiers" type="oai:ListIdentifiersType"/>
      <element name="ListRecords" type="oai:ListRecordsType"/>
    </choice>
  </sequence>
</complexType>

<complexType name="requestType">
  <annotation>
    <documentation>Define requestType, indicating the protocol request that 
    led to the response. Element content is BASE-URL, attributes are arguments 
    of protocol request, attribute-values are values of arguments of protocol 
    request</documentation>
  </annotation>
  <simpleContent>
    <extension base="anyURI">
      <attribute name="verb" type="oai:verbType" use="optional"/>
      <attribute name="identifier" type="oai:identifierType" use="optional"/>
      <attribute name="metadataPrefix" type="oai:metadataPrefixType" use="optional"/>
      <attribute name="from" type="oai:UTCdatetimeType" use="optional"/>
      <attribute name="until" type="oai:UTCdatetimeType" use="optional"/>
      <attribute name="set" type="oai:setSpecType" use="optional"/>
      <attribute name="resumptionToken" type="string" use="optional"/>
    </extension>
  </simpleContent>
</complexType>

<simpleType name="verbType">
  <restriction base="string">
    <enumeration value="Identify"/>
    <enumeration value="ListMetadataFormats"/>
    <enumeration value="ListSets"/>
    <enumeration value="GetRecord"/>
    <enumeration value="ListIdentifiers"/>
    <enumeration value="ListRecords"/>
  </restriction>
</simpleType>

<!-- define OAI-PMH error conditions -->
<!-- =============================== -->

<complexType name="OAI-PMHerrorType">
  <simpleContent>
    <extension base="string">
      <attribute name="code" type="oai:OAI-PMHerrorcodeType" use="required"/>
    </extension>
  </simpleContent>
</complexType>

<simpleType name="OAI-PMHerrorcodeType">
  <restriction base="string">
    <enumeration value="cannotDisseminateFormat"/>
    <enumeration value="idDoesNotExist"/>
    <enumeration value="badArgument"/>
    <enumeration value="badVerb"/>
    <enumeration value="noMetadataFormats"/>
    <enumeration value="noRecordsMatch"/>
    <enumeration value="badResumptionToken"/>
    <enumeration value="noSetHierarchy"/>
  </restriction>
</simpleType>

<!-- define OAI-PMH verb containers -->
<!-- ============================== -->

<complexType name="IdentifyType">
  <sequence>
    <element name="repositoryName" type="string"/>
    <element name="baseURL" type="anyURI"/>
    <element name="protocolVersion" type="oai:protocolVersionType"/>
    <element name="adminEmail" type="oai:emailType" maxOccurs="unbounded"/>
    <element name="earliestDatestamp" type="oai:UTCdatetimeType"/>
    <element name="deletedRecord" type="oai:deletedRecordType"/>
    <element name="granularity" type="oai:granularityType"/>
    <element name="compression" type="string" minOccurs="0" maxOccurs="unbounded"/>
    <element name="description" type="oai:descriptionType" 
             minOccurs="0" maxOccurs="unbounded"/>
  </sequence>
</complexType>

<complexType name="ListMetadataFormatsType">
  <sequence>
    <element name="metadataFormat" type="oai:metadataFormatType" maxOccurs="unbounded"/>
  </sequence>
</complexType>

<complexType name="ListSetsType">
  <sequence>
    <element name="set" type="oai:setType" maxOccurs="unbounded"/>
    <element name="resumptionToken" type="oai:resumptionTokenType" minOccurs="0"/>
  </sequence>
</complexType>

<complexType name="GetRecordType">
  <sequence>
    <element name="record" type="oai:recordType"/>
  </sequence>
</complexType>

<complexType name="ListRecordsType">
  <sequence>
    <element name="record" type="oai:recordType" maxOccurs="unbounded"/>
    <element name="resumptionToken" type="oai:resumptionTokenType" minOccurs="0"/>
  </sequence>
</complexType>

<complexType name="ListIdentifiersType">
  <sequence>
    <element name="header" type="oai:headerType" maxOccurs="unbounded"/>
    <element name="resumptionToken" type="oai:resumptionTokenType" minOccurs="0"/>
  </sequence>
</complexType>

<!-- define basic types used in replies to 
     GetRecord, ListRecords, ListIdentifiers -->
<!-- ======================================= -->

<complexType name="recordType">
  <annotation>
    <documentation>A record has a header, a metadata part, and
      an optional about container</documentation>
  </annotation>
  <sequence>
    <element name="header" type="oai:headerType"/>
    <element name="metadata" type="oai:metadataType" minOccurs="0"/>
    <element name="about" type="oai:aboutType" minOccurs="0" maxOccurs="unbounded"/>
  </sequence>
</complexType>

<complexType name="headerType">
  <annotation>
    <documentation>A header has a unique identifier, a datestamp,
      and setSpec(s) in case the item from which
      the record is disseminated belongs to set(s).
      the header can carry a deleted status indicating
      that the record is deleted.</documentation>
  </annotation>
  <sequence>
    <element name="identifier" type="oai:identifierType"/>
    <element name="datestamp" type="oai:UTCdatetimeType"/>
    <element name="setSpec" type="oai:setSpecType" minOccurs="0" maxOccurs="unbounded"/>
  </sequence>
  <attribute name="status" type="oai:statusType" use="optional"/>
</complexType>

<simpleType name="identifierType">
  <restriction base="anyURI"/>
</simpleType>

<simpleType name="statusType">
  <restriction base="string">
    <enumeration value="deleted"/>
  </restriction>
</simpleType>

<complexType name="metadataType">
  <annotation>
    <documentation>Metadata must be expressed in XML that complies
     with another XML Schema (namespace=#other). Metadata must be 
     explicitly qualified in the response.</documentation>
  </annotation>
  <sequence>
    <any namespace="##other" processContents="strict"/>
  </sequence>
</complexType>

<complexType name="aboutType">
  <annotation>
    <documentation>Data "about" the record must be expressed in XML
    that is compliant with an XML Schema defined by a community.</documentation>
  </annotation>
  <sequence>
    <any namespace="##other" processContents="strict"/>
  </sequence>
</complexType>

<complexType name="resumptionTokenType">
  <annotation>
    <documentation>A resumptionToken may have 3 optional attributes
     and can be used in ListSets, ListIdentifiers, ListRecords
     responses.</documentation>
  </annotation>
  <simpleContent>
    <extension base="string">
      <attribute name="expirationDate" type="dateTime" use="optional"/>
      <attribute name="completeListSize" type="positiveInteger" use="optional"/>
      <attribute name="cursor" type="nonNegativeInteger" use="optional"/>
    </extension>
  </simpleContent>
</complexType>

<complexType name="descriptionType">
  <annotation>
    <documentation>The descriptionType is used for the description
    element in Identify and for setDescription element in ListSets.
    Content must be compliant with an XML Schema defined by a 
    community.</documentation>
  </annotation>
  <sequence>
    <any namespace="##other" processContents="strict"/>
  </sequence>
</complexType>

<simpleType name="UTCdatetimeType">
  <annotation>
    <documentation>Datestamps are to either day (type date)
    or to seconds granularity (type oai:UTCdateTimeZType)</documentation>
  </annotation>
  <union memberTypes="date oai:UTCdateTimeZType"/>
</simpleType>

<simpleType name="UTCdateTimeZType">
  <restriction base="dateTime">
    <pattern value=".*Z"/>
  </restriction>
</simpleType>

<!-- define types used for Identify verb only -->
<!-- ======================================== -->

<simpleType name="protocolVersionType">
  <restriction base="string">
    <enumeration value="2.0"/>
  </restriction>
</simpleType>

<simpleType name="emailType">
  <restriction base="string">
    <pattern value="\S+@(\S+\.)+\S+"/>
  </restriction>
</simpleType>

<simpleType name="deletedRecordType">
  <restriction base="string">
    <enumeration value="no"/>
    <enumeration value="persistent"/>
    <enumeration value="transient"/>
  </restriction>
</simpleType>

<simpleType name="granularityType">
  <restriction base="string">
    <enumeration value="YYYY-MM-DD"/>
    <enumeration value="YYYY-MM-DDThh:mm:ssZ"/>
  </restriction>
</simpleType>

<!-- define types used for ListMetadataFormats verb only -->
<!-- =================================================== -->

<complexType name="metadataFormatType">
  <sequence>
    <element name="metadataPrefix" type="oai:metadataPrefixType"/>
    <element name="schema" type="anyURI"/>
    <element name="metadataNamespace" type="anyURI"/>
  </sequence>
</complexType>

<simpleType name="metadataPrefixType">
  <restriction base="string">
    <pattern value="[A-Za-z0-9\-_\.!~\*'\(\)]+"/>
  </restriction>
</simpleType>

<!-- define types used for ListSets verb -->
<!-- =================================== -->

<complexType name="setType">
  <sequence>
    <element name="setSpec" type="oai:setSpecType"/>
    <element name="setName" type="string"/>
    <element name="setDescription" type="oai:descriptionType" 
             minOccurs="0" maxOccurs="unbounded"/>
  </sequence>
</complexType>

<simpleType name="setSpecType">
  <restriction base="string">
    <pattern value="([A-Za-z0-9\-_\.!~\*'\(\)])+(:[A-Za-z0-9\-_\.!~\*'\(\)]+)*"/>
  </restriction>
</simpleType>

</schema>