<nw:nameworld xmlns:nw="http://openuri.org/nameworld"
              xmlns:foo="http://foo.com/"
              xmlns:bar="http://bar.com/">

  <nw:island targetNamespace="http://foo.com/">
    <nw:location name="foocity">
      <nw:reference to="bar:barcity"/>
      <nw:reference to="foo:footown"/>
      <nw:reference to="bar:barvillage"/>
    </nw:location>
    <nw:location name="footown">
      <nw:reference to="bar:bartown"/>
      <nw:reference to="foo:foovillage"/>
    </nw:location>
    <nw:location name="foovillage">
      <nw:reference to="bar:barvillage"/>
    </nw:location>
  </nw:island>

  <nw:island targetNamespace="http://bar.com/">
    <nw:location name="barcity">
      <nw:reference to="foo:foocity"/>
      <nw:reference to="bar:bartown"/>
      <nw:reference to="foo:foovillage"/>
    </nw:location>
    <nw:location name="bartown">
      <nw:reference to="foo:footown"/>
      <nw:reference to="bar:barvillage"/>
    </nw:location>
    <nw:location name="barvillage">
      <nw:reference to="foo:foovillage"/>
    </nw:location>
  </nw:island>
</nw:nameworld>