Question: What did Thomas Edison and Joesph Swan invent?
Answer(s):
answer: Incandescent light bulb

SPARQL query:
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SELECT DISTINCT ?x
WHERE {
FILTER (?x != ns:m.07bty)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
ns:m.07bty ns:law.inventor.inventions ?x .
?x ns:law.invention.inventor ns:m.0109ts . 
}