By Roger Zelazny ,
By O. T. Nelson ,
By Andre Norton ,
By Doris Lessing ,
By Jerry Pournelle ,
By Clifford D. Simak ,
By John Varley ,
By Keith Laumer ,
By Marion Zimmer Bradley ,
By Arthur C. Clarke ,
By John Wyndham ,
By Christopher Priest ,
By Doris Piserchia ,
By Peter Jenkins ,
By Wilma Dykeman ,
By Frederik Pohl ,
By Margaret Sprout , Harold Sprout ,
By Ben Bova ,
By Jack Vance ,
By Joe Haldeman ,
By James P. Hogan ,
By D. F. Jones ,
By T. C. McLuhan ,
or
