What is {spouse} of {Ilona Staller} that is {start time} is {1991-0-0} ?
At the start of 1991, who was Ilona Staller married to?
Who was the spouse of Ilona Staller at the beginning of 1991?
SELECT ?c WHERE { FILTER ( CONTAINS ( YEAR ( ?t ) , '1991' ) ) . resource:Ilona_Staller property:spouse ?l . ?l property:start_time ?t . ?l property:spouse ?c }
select distinct ?obj  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q49941> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P26> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
?statement <http://www.wikidata.org/entity/P580> <1991-0-0>
} 

SELECT ?obj WHERE { wd:Q49941 p:P26 ?s . ?s ps:P26 ?obj . ?s pq:P580 ?x filter(contains(YEAR(?x),'1991')) }