P5: Linee guida per la codifica e l'interscambio del testo elettronico

<rng:element name="msIdentifier">
<rng:ref name="att.global.attributes"/>
<rng:group>
 <rng:choice>
  <rng:group>
<!--    <rng:optional>
      <rng:ref name="country"/>
    </rng:optional>
    <rng:optional>
      <rng:ref name="region"/>
    </rng:optional>
    <rng:ref name="settlement"/>
-->
   <rng:ref name="model.placeNamePart_sequenceOptional"/>
   <rng:optional>
    <rng:ref name="institution"/>
   </rng:optional>
   <rng:ref name="repository"/>
   <rng:optional>
    <rng:ref name="collection"/>
   </rng:optional>
   <rng:optional>
    <rng:ref name="idno"/>
   </rng:optional>
  </rng:group>
  <rng:ref name="msName"/>
 </rng:choice>
 <rng:zeroOrMore>
  <rng:choice>
   <rng:ref name="altIdentifier"/>
   <rng:ref name="msName"/>
  </rng:choice>
 </rng:zeroOrMore>
</rng:group>
</rng:element>

element msIdentifier
{
   att.global.attributes,
   (
      (
         (
            model.placeNamePart_sequenceOptional,
            institution?,
            repository,
            collection?,
            idno?
         )
       | msName
      ),
      ( altIdentifier | msName )*
   )
}