what is the {start time} for {Leslie Lamport} has {employer} as {Microsoft Research} ?
When did Leslie Lamport's employment for Microsoft Research begin?
When did Leslie Lamport start working for Microsoft Research?
SELECT ?c WHERE { ?o property:start_time ?c . resource:Leslie_Lamport property:employer ?o . ?o property:employer resource:Microsoft_Research }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q92613> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P108> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q1144725> .
?statement <http://www.wikidata.org/entity/P580> ?value. 
} 

SELECT ?value WHERE { wd:Q92613 p:P108 ?s . ?s ps:P108 wd:Q1144725 . ?s pq:P580 ?value}