The demon Valefar appears in the grimoires Book of Incantations, The Discoverie of Witchcraft, The Grand Grimoire, Pseudomonarchia Daemonum, and The Lesser Key of Solomon
From The Lesser Key of Solomon, Crowley/Mathers edition:
Valefar
The Sixth Spirit is Valefor. He is a mighty Duke, and appeareth in the shape of a Lion with an Ass's head, bellowing. He is a good Familiar, but tempteth them he is a familiar of to steal. He governeth 1o Legions of Spirits. His Seal is this, which is to be worn, whether thou wilt have him for a Familiar, or not.
