what is the {start time} for {Roman Abramovich} has {spouse} as {Irina Abramovich} ?
At what time did Roman Abramovich marry Irina Abramovich?
When did Roman Abramovich marry Irina Abramovich?
SELECT ?r WHERE { ?a property:spouse resource:Irina_Abramovich . resource:Roman_Abramovich property:spouse ?a . ?a property:start_time ?r }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q171428> .
?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/Q46109451> .
?statement <http://www.wikidata.org/entity/P580> ?value. 
} 

SELECT ?value WHERE { wd:Q171428 p:P26 ?s . ?s ps:P26 wd:Q46109451 . ?s pq:P580 ?value}