<rdf:RDF  xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
          xmlns:skos="http://www.w3.org/2004/02/skos/core#">
        
  <!-- Examples adapted from UK GCL:
  http://www.govtalk.gov.uk/schemasstandards/gcl.asp
  ... -->        
          
   <skos:Concept rdf:about="http://www.example.com/GCL/concepts#462">
      <skos:prefLabel>Tourism</skos:prefLabel>
      <skos:broader rdf:resource="http://www.example.com/GCL/concepts#616"/>
      <skos:broader rdf:resource="http://www.example.com/GCL/concepts#705"/>
   </skos:Concept>

   <skos:Concept rdf:about="http://www.example.com/GCL/concepts#616">
      <skos:prefLabel>Arts, recreation and travel</skos:prefLabel>
   </skos:Concept>

   <skos:Concept rdf:about="http://www.example.com/GCL/concepts#705">
      <skos:prefLabel>Distribution and service industries</skos:prefLabel>
   </skos:Concept>

  <!-- Examples adapted from PACS:
  http://www.aip.org/pacs/
  ... -->
  
  <skos:Concept rdf:about="http://www.example.com/PACS/concepts#31.15.Ja">
    <skos:prefLabel>Hyperspherical methods</skos:prefLabel>
    <skos:broader rdf:resource="http://www.example.com/PACS/concepts#31.15.-p"/>
  </skos:Concept>  

  <skos:Concept rdf:about="http://www.example.com/PACS/concepts#31.15.-p">
    <skos:prefLabel>Calculations and mathematical techniques in atomic and molecular physics</skos:prefLabel>
    <skos:broader rdf:resource="http://www.example.com/PACS/concepts#31."/>
  </skos:Concept>  

  <skos:Concept rdf:about="http://www.example.com/PACS/concepts#31.">
    <skos:prefLabel>Electronic structure of atoms and molecules: theory</skos:prefLabel>
    <skos:broader rdf:resource="http://www.example.com/PACS/concepts#30."/>
  </skos:Concept>  

  <skos:Concept rdf:about="http://www.example.com/PACS/concepts#30.">
    <skos:prefLabel>ATOMIC AND MOLECULAR PHYSICS</skos:prefLabel>
  </skos:Concept>  

</rdf:RDF>