what is the {end time} for {Association for Computing Machinery} has {chairperson} as {Maria Klawe} ?
Maria Klawe was replaced as chairperson for the Association for Computing Machinery in which year?
In what year did Maria Klawe cease being a chairperson for the Association for Computing Machinery?
SELECT ?t WHERE { ?u property:end_time ?t . ?u property:chairperson resource:Maria_Klawe . resource:Association_for_Computing_Machinery property:chairperson ?u }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q127992> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P488> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q11754> .
?statement <http://www.wikidata.org/entity/P582> ?value. 
} 

SELECT ?value WHERE { wd:Q127992 p:P488 ?s . ?s ps:P488 wd:Q11754 . ?s pq:P582 ?value}