Question: Who held the post of Secretary of State during the presidency of Richard Nixon and took this position on 1969-01-22?
Answer(s):
answer: William P. Rogers

SPARQL query:
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT ?x
WHERE {
FILTER (?x != ns:m.06c97)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
ns:m.06c97 ns:government.political_appointer.appointees ?y .
?y ns:government.government_position_held.office_holder ?x .
?y ns:government.government_position_held.basic_title ns:m.0789n .
?x ns:government.politician.government_positions_held ?c .
?c ns:government.government_position_held.from "1969-01-22"^^xsd:dateTime . 
}