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 ?
Sentence (from "Percy Jackson &amp; the Olympians"): Five supplementary books, along with three graphic novels, have also been released.
Relevant evidence: No