<grammar xmlns=“relaxng.org/ns/structure/1.0” datatypeLibrary=“www.w3.org/2001/XMLSchema-datatypes”>

<include href="simple.rng"/>
<define name="attributes">
  <element name="attributes" ns="http://cpee.org/ns/properties/2.0">
    <zeroOrMore>
      <ref name="simple"/>
    </zeroOrMore>
  </element>
</define>

</grammar>