Doctor Who and the Infinity Doctors (in-universe)

 was a book that was cited when the Eighth Doctor mentioned that he was unsure if he had been exiled to his homeplanet, among other possiblities. (PROSE: Bafflement and Devotion)

Behind the scenes
In A Lady Doctor, a partially licenced Iris Wildthyme short story, Iris Wildthyme mentions to her companion Andrew that the Doctor had previously been a woman in The Infinity Doctors.