what is the {start time} for {Pablo Casals} has {spouse} as {Marta Casals Istomin} ?
On what date did Pablo Casals wed Marta Casals Istomin?
When did Pablo Casals marry Marta Casals Istomin?
SELECT ?r WHERE { resource:Pau_Casals property:spouse ?z . ?z property:start_time ?r . ?z property:spouse resource:Marta_Casals_Istomin }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q208537> .
?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> <http://wikidata.dbpedia.org/resource/Q6774099> .
?statement <http://www.wikidata.org/entity/P580> ?value. 
} 

SELECT ?value WHERE { wd:Q208537 p:P26 ?s . ?s ps:P26 wd:Q6774099 . ?s pq:P580 ?value}