I wanted to say "Person XXXX has a Personal Profile Document at http://www.example.org/foaf/392j92j3".
There is a foaf:primaryTopic property, but there isn't an inverse. Also, it's domain is foaf:Document, which is too broad. I really want to link a foaf:Person to a foaf:PersonalProfileDocument.
So I've embedded the following RDF into all the Flickr FOAF:
<rdfs:domain rdf:resource="http://xmlns.com/foaf/0.1/Person" />
<rdfs:range rdf:resource="http://xmlns.com/foaf/0.1/PersonalProfileDocument" />