The Gemini Problem, a Study in Darkover by Walter Breen is a "Fanzine dedicated to Marion Zimmer Bradley's fantasy works. It was originally published as a Christmas gift in 1971, but has been revised and republished for the Friends of Darkover in 1975. It offers tips on how to write like MZB.". A copy of the 1978 issue is held in the VCU Libraries M. Thomas Inge Collection of Comic Arts Reference Journals.