what is the {end time} for {Palermo} has {head of government} as {Leoluca Orlando} ?
At which point in time was Leoluca Orlando the head of Palermo?
When was Leoluca Orlando the head of Palermo?
SELECT ?e WHERE { ?f property:end_time ?e . resource:Palermo property:head_of_government ?f . ?f property:head_of_government resource:Leoluca_Orlando }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q2656> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P6> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q703503> .
?statement <http://www.wikidata.org/entity/P582> ?value. 
} 

SELECT ?value WHERE { wd:Q2656 p:P6 ?s . ?s ps:P6 wd:Q703503 . ?s pq:P582 ?value}