The Lesser Key of Solomon
by S.L. MacGregor Mathers and Aleister Crowley
This edition of the Lesser Key of Solomon is based on manuscripts from the British Museum, edited by two prominent occultists. Although Mathers took lead on the body of the text, Crowley's literary fingerprints are all over this book, such as the polite sniping at A.E. Waite, the Preliminary Invocation, and the essay The Initiated Interpretation of Ceremonial Magic, which is classic Crowley.
This is a considerably cleaned up and modernized version of the Lesser Key, which is obviously intended to be used as a working document for serious magicians, rather than a rigorous transcription of the source manuscripts. However, the information presented here dovetails with the other Goetic grimoires and this version is considered one of the best of this literature.