Question: The Toccata and Fugue in D minor, BWV 538, is an organ piece by Johann Sebastian Bach, like the better-known BWV 565, the Toccata and Fugue in D minor, BWV 565, is a piece of organ music written, according to its oldest extant sources, by who?
{'answer': 'Johann Sebastian Bach', 'supporting_facts': [['Toccata and Fugue in D minor, BWV 538', 0], ['Toccata and Fugue in D minor, BWV 565', 0]]}