<prov:document
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema"
    xmlns:prov="http://www.w3.org/ns/prov#"
    xmlns:ex="http://example.com/ns/ex#">

  <prov:collection prov:id="ex:c1" />

</prov:document>
