@prefix : <foo://bla#> .
 @prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#>.
 @prefix xsd: <http://www.w3.org/2001/XMLSchema#>.
 :birthdate rdfs:range xsd:date.
 :john a :Person; :name "John"; :age 32;
  :birthdate "1970-12-31"^^xsd:date .
 :alice a :Person; :name "Alice"; :birthdate "2000-01-01"^^xsd:date .