Project(Filter(regex(?creator, "darnton", "i") ,
               BGP( ?s <http://purl.org/ontology/bibo/cites> ?source .
                    ?source <http://www.idemb.org/idemb#creator> ?creator .
                    ?source <http://www.idemb.org/idemb#title> ?title)),
        {?s, ?title, ?creator})