The demon Focalor appears in the grimoires Book of Incantations, The Discoverie of Witchcraft, Pseudomonarchia Daemonum, and The Lesser Key of Solomon
From The Lesser Key of Solomon, Crowley/Mathers edition:
The Forty-first Spirit is Focalor, or Forcalor, or Furcalor. He is a Mighty Duke and Strong. He appeareth in the Form of a Man with Gryphon's Wings. His office is to slay Men, and to drown them in the Waters, and to overthrow Ships of War, for he hath Power over both Winds and Seas; but he will not hurt any man or thing if he be commanded to the contrary by the Exorcist. He also hath hopes to return to the Seventh Throne after 1,000 years. He governeth 30 Legions of Spirits, and his Seal is this, etc.