libopc/third_party/libxml2-2.7.7/test/relaxng/tutor11_1_1.xml

<grammar xmlns="http://relaxng.org/ns/structure/1.0">

  <start>
    <ref name="anyElement"/>
  </start>

  <define name="anyElement">
    <element>
      <anyName/>
      <zeroOrMore>
	<choice>
	  <attribute>
	    <anyName/>
	  </attribute>
	  <text/>
	  <ref name="anyElement"/>
	</choice>
      </zeroOrMore>
    </element>
  </define>

</grammar>