<xs:element minOccurs="0" maxOccurs="unbounded" name="Keyword" >
  <xs:complexType>
    <xs:simpleContent>
      <xs:extension base="xs:string">
        <xs:attribute name="whiteSpace">
          <xs:simpleType>
            <xs:restriction base="xs:string">
              <xs:enumeration value="preserve"/>
              <xs:enumeration value="replace"/>
              <xs:enumeration value="collapse"/>
            </xs:restriction>
          </xs:simpleType>
        </xs:attribute>
        <xs:attribute name="alias" type="xs:token" use="optional"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>
</xs:element>