Question: The Heroes of Olympus is a pentalogy of adventure, mythological fiction and fantasy novels by American author Rick Riordan that collectively form a sequel series to the Percy Jackson & the Olympians series, a pentalogy of adventure and mythological fiction books written by which American author ?
{'answer': 'Rick Riordan', 'supporting_facts': [['The Heroes of Olympus', 0], ['Percy Jackson &amp; the Olympians', 0]]}