Introduction (Possible Worlds of SF)

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Overview:

Title: Introduction (Possible Worlds of SF)
Author: Groff Conklin
Year: 1951
Type: Essays

Editions/Publications:

Unknown. Possible Worlds of Science Fiction (Unknown, Groff Conklin, Vanguard Press, $2.95, xi+372 pages, Hardcover, Anthology)
Unknown. Possible Worlds of Science Fiction (Unknown, Groff Conklin, Grayson & Grayson, 9/6, 254 pages, Hardcover, Anthology)