SELECT DISTINCT COUNT(?uri) WHERE { ?x <http://dbpedia.org/ontology/publisher> <http://dbpedia.org/resource/Doubleday_(publisher)> . ?x <http://dbpedia.org/ontology/nonFictionSubject> ?uri . }
How many subjects are covered in the publications of Doubleday?
SELECT DISTINCT COUNT ( ?r ) WHERE { ?k property:publisher resource:Doubleday_(publisher) . ?k property:non_fiction_subject ?r . }
143
There are [143] non-fiction subjects of the books published by Doubleday.
There is [143] non-fiction in the Double Day books.