Was a paper not not co-authored by Gransden, I. R. and Steve W. Beet?
Didn't I. R. Gransden and Steve W. Beet not co-author a paper?
ASK { ?x <https://dblp.org/rdf/schema#authoredBy> <https://dblp.org/pid/72/4421> . ?x <https://dblp.org/rdf/schema#authoredBy> <https://dblp.org/pid/91/9335> }
<https://dblp.org/pid/72/4421> <https://dblp.org/pid/91/9335>