What is the {opera} for {librettist} of {Gertrude Stein}
Gertrude Stein is the librettist of which opera?
Gertrude Stein is the librettist of which opera?
SELECT DISTINCT ?u WHERE { ?u rdf:type ontology:opera . ?u property:librettist resource:Gertrude_Stein }
select distinct ?subj where { ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> ?subj . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P87> . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q188385> . ?subj <http://www.wikidata.org/entity/P31> <http://wikidata.dbpedia.org/resource/Q1344> } 
 select distinct ?sbj where { ?sbj wdt:P87 wd:Q188385 . ?sbj wdt:P31 wd:Q1344 } 
Four Saints in Three Acts The Mother of Us All