Question: Where has the artwork referenced by the title of the novel "The Garden of Unearthly Delights" housed? 
Sentence (from "The Garden of Earthly Delights"): The Garden of Earthly Delights is the modern title given to a triptych painted by the Early Netherlandish master Hieronymus Bosch, housed in the Museo del Prado in Madrid since 1939.
Relevant evidence: Yes