GURPS Witch World
Role Playing Game World Book written with Ben W. Miller
(US Trade Paperback, Steve Jackson Games, 1989)
This world book in Steve Jackson's Generic Universal Role Playing System (GURPS) is the most definitive guide to Andre Norton's Witch World series that has been published. Produced with the full cooperation of Andre Norton, this book is the reference which Andre Norton recommended for other writers writing in her world.
GURPS Witch World is currently out of print.