of Atomigeddon / Walter Ernsting (as Clark Darlton) Atlan #2: Flight from Tarkihl 66121 SF Winfried Scholz (as W.W. Shols) Perry Rhodan Robot Threat: New York / Hanns Kneifel (as Hans Kneifel) Atlan #3: Pale Country Pursuit 66128 SF K. H. Scheer Perry Rhodan Atlan #4: The Crystal Prince / Walter Ernsting (as Clark Darlton) Atlan #5: War of the Ghosts 67021 SF Marion Zimmer BradleyThe Planet Savers / The Sword of Aldones (April 1980) 67025 SF Marion Zimmer BradleyThe Planet Savers / The Sword of Aldones (1983) 67026 SF Marion Zimmer BradleyThe Planet Savers / The Sword of Aldones (August 1985) 67027 SF Marion Zimmer BradleyThe Planet Savers / The Sword of Aldones (1987) 72401 SF A. Bertram Chandler The Rim Gods / The Dark Dimension (August 1978) 72402 SF A. Bertram Chandler The Rim of Space / The Ship From Outside (November 1979) 72403 SF A. Bertram Chandler The Rim Gods / The Dark Dimension (September 1981) 73100 SF A. Bertram Chandler The Road to the Rim / The Hard Way Up (April 1978) 73101 SF A. Bertram Chandler The Road to the Rim / The Hard Way Up (1979) 73102 SF A. Bertram Chandler The Road to the Rim / The Hard Way Up (September 1981) 73390 SF Avram Davidson Rogue Dragon / The Kar-Chee Reign (March 1979) 78537 SF Robert Sheckley The Status Civilization / Notions: Unlimited (November 1979) 81237 SF Gordon R. Dickson Time to Teleport / Delusion World (July 1981) 86495 SF L. Sprague de Camp The Tower of Zanid / The Virgin of Zesh (February 1983) References Ace Image Library. Contains images of most covers for the doubles in all genres, as well as many of the single titles. Bookscans. Contains numerous images of the Ace covers. Corrick, James A. Double Your Pleasure: The Ace SF Double, Gryphon Books, 1989. . A historical article, followed by a checklist of the SF Doubles, giving prior publication history for the contents of each one. Thiessen, J. Grant Science Fiction Collector #1, Pandora's Books, 1976. Includes Ace Double checklist. Thiessen, J. Grant Science Fiction Collector #2, Pandora's Books, date unknown. Includes errata for checklist in #1. Tuck, Donald H. The Encyclopedia of Science Fiction and Fantasy: Volume 3, Advent: Publishers, Inc., 1982. . Lists all ACE sf titles, single and double, published through 1968. The following references have not been seen but cover the Ace Doubles: