Question: What European Union country once used the Danish krone as its domestic currency?
Answer(s):
answer: Denmark

SPARQL query:
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT ?x
WHERE {
FILTER (?x != ns:m.0_6t_z8)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
ns:m.0_6t_z8 ns:organization.membership_organization.members ?y .
?y ns:organization.organization_membership.member ?x .
?x ns:location.country.currency_used ns:m.01j9nc . 
}