select ?dd, ?date, ?x, ?mb  from 
 file:rdf/000068.rdf 
 where (dc::description ?x ?dd) (dc::date ?x ?date) 
  (foaf::depiction ?per ?x) (foaf::mbox ?per ?mb) 
 and ?mb ne 'mailto:clare@example.com' 
 using dc for http://purl.org/dc/elements/1.1/ 
 foaf for http://xmlns.com/foaf/0.1/