P5: Guidelines for Electronic Text Encoding and Interchange

<rng:element name="titleStmt">
 <rng:ref name="att.global.attributes"/>
 <rng:group>
  <rng:oneOrMore>
   <rng:ref name="title"/>
  </rng:oneOrMore>
  <rng:zeroOrMore>
   <rng:choice>
    <rng:ref name="author"/>
    <rng:ref name="editor"/>
    <rng:ref name="sponsor"/>
    <rng:ref name="funder"/>
    <rng:ref name="principal"/>
    <rng:ref name="respStmt"/>
   </rng:choice>
  </rng:zeroOrMore>
 </rng:group>
</rng:element>

element titleStmt
{
   att.global.attributes,
   ( title+, ( author | editor | sponsor | funder | principal | respStmt )* )
}