<xs:complexType name="dateType" >
  <xs:choice>
    <xs:element name="exact" type="simpleDate"/>
    <xs:sequence>
      <xs:element name="begin" type="simpleDate"/>
      <xs:element name="end" type="simpleDate"/>
    </xs:sequence>
    <xs:sequence>
      <xs:element name="from">
        <xs:complexType>
          <xs:simpleContent>
            <xs:extension base="simpleDate"/>
          </xs:simpleContent>
        </xs:complexType>
      </xs:element>
      <xs:element minOccurs="0" maxOccurs="1" name="to" type="simpleDate"/>
    </xs:sequence>
    <xs:element name="to" type="simpleDate"/>
    <xs:element name="text" type="xs:normalizedString"/>
  </xs:choice>
</xs:complexType>