<xs:element name="volume">
  <xs:annotation>
    <xs:documentation xml:lang="en">Introduces the number used for the volume of a journal or a series of publications</xs:documentation>
    <xs:appinfo>
      <identifier>http://w3id.org/meta-share/meta-share/volume</identifier>
      <label xml:lang="en">volume</label>
    </xs:appinfo>
  </xs:annotation>
  <xs:simpleType>
    <xs:restriction base="xs:string">
      <xs:maxLength value="20"/>
    </xs:restriction>
  </xs:simpleType>
</xs:element>