Doctor Who and an Unearthly Child was a book written by Terrance Dicks which the Eighth Doctor claimed contradicted Doctor Who in an Exciting Adventure with the Daleks (also called Doctor Who and the Dead Planet). (PROSE: Bafflement and Devotion)
Behind the scenes
This is a in-universe counterpart of the real world Target Books novelisation Doctor Who and an Unearthly Child that exists within the Doctor's universe. It was referenced in Bafflement and Devotion as one of Iris Wildthyme's possessions, providing commentary upon continuity and lack thereof, as well as it being a fictional citation.