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

<rng:element name="forestGrp">
<rng:ref name="att.global.attributes"/>
<rng:optional>
 <rng:attribute name="type">
  <rng:ref name="data.enumerated"/>
 </rng:attribute>
</rng:optional>
<rng:oneOrMore>
 <rng:ref name="forest"/>
</rng:oneOrMore>
</rng:element>

element forestGrp
{
   att.global.attributes,
   attribute type { data.enumerated }?,
   forest+
}