Question: When did Al-Mansur end his rule as Abbasid Caliph?
Paraphrase: On What data did Al- Mansur end his rule as Abbasid Caliph?
SPARQL (Wikidata): SELECT ?value WHERE { wd:Q31066 p:P39 ?s . ?s ps:P39 wd:Q28541943 . ?s pq:P582 ?value}