Worlds of If (If, May 1960)

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Overview:

Title: Worlds of If (If, May 1960)
Author: Frederik Pohl
Year: 1960
Type: Essays
Series: Worlds of If (If)

Editions/Publications:

Unknown. If, May 1960 (Unknown, Frederik Pohl, Digest Productions Corporation; New York, $0.35, 132 pages, digest, MAGAZINE)
Unknown. If, #4 [UK] (Unknown, Frederik Pohl, Strato Publications, 2/-, 132 pages, digest, MAGAZINE)