what is the {end time} for {Abu Bakr} has {position held} as {Rashidun Caliphate} ?
On what date did Abu Bakr cease to be Rashidun Caliphate?
When did Abu Bakr stop being Rashidun Caliphate?
SELECT ?g WHERE { resource:Abu_Bakr property:position_held ?g . ?g property:end_time ?g . ?g property:position_held resource:Rashidun_Caliphate }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q334923> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P39> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q12490507> .
?statement <http://www.wikidata.org/entity/P582> ?value. 
} 

SELECT ?value WHERE { wd:Q334923 p:P39 ?s . ?s ps:P39 wd:Q12490507 . ?s pq:P582 ?value}