what is the {start time} for {Cameroon} has {member of} as {International Finance Corporation} ?
At what time did Cameroon become a member of the International Fincance Corporation?
When did Cameroon become a member of the International Finance Corporation?
SELECT ?n WHERE { ?j property:start_time ?n . resource:Cameroon property:member_of ?j . ?j property:member_of resource:International_Finance_Corporation }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q1009> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P463> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q656801> .
?statement <http://www.wikidata.org/entity/P580> ?value. 
} 

SELECT ?value WHERE { wd:Q1009 p:P463 ?s . ?s ps:P463 wd:Q656801 . ?s pq:P580 ?value}