Liber Immanis Monstrorum
The Monster Book of Monsters, by Professor Cuvee of Unseen University.
This might be a play on one of the many Dungeon-master manuals available for the role-playing game Dungeons and Dragons. There is a very large thick Bestiary of known and semi-mythical animals, together with lists of demons, demiurges, monstrosities, flukes, and ill-tempered sendings derived from most of the world's major mythologies and several fictional ones. It may even be called the Monster Companion.
A similarly titled book, the "Monster Book of Monsters" is used as a text book by Harry Potter in J.K. Rawling's novel, Harry Potter and the Prisoner of Azkaban. Perhaps one author is paying tribute to another?