I want to model an RDF/XML statement about a publication (in namespace, say, 'myns'). I know that this publication is known under a given URN. What is the propper way to reference that URN in RDF? I can think of a number of different ways to do this, e.g.:
<myns:Publication rdf:about="item42">
<myns:urn>urn:abc:xy:123-456789</myns:urn>
</myns:Publication>
<myns:Publication rdf:about="item42">
<rdfs:seeAlso>urn:abc:xy:123-456789</rdfs:seeAlso>
</myns:Publication>
<myns:Publication rdf:about="item42">
<owl:sameAs>urn:abc:xy:123-456789</owl:sameAs>
</myns:Publication>
<myns:Publication rdf:about="item42">
<owl:sameAs rdf:reference="urn:abc:xy:123-456789" />
</myns:Publication>
What is the right (i.e., the most beneficial) way of giving an URN reference?