Katherine Kurtz
Katherine Kurtz (Katherine Irene Kurtz) is an American fantasy author. She was born 1944. She is best known for the Deryni novels.
Deryni Magic is also known as Deryni Magic: A Grimoire.
Here, for the first time, the secrets of the Deryni, that mysterious race of wizards and healers blessed with arcane mental powers, are revealed.