Retroactive

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Overview:

Title: Retroactive
Author: Bob Shaw
Year: 1972
Type: Short Fiction
Series: A.E.S.O.P.

Variant Titles:

Editions/Publications:

Unknown. Universe 2 (Unknown, Bob Shaw, Ace Books, ISBN-10: 0441846017, $0.95, 255 pages, Paperback, Anthology)
Unknown. Universe 2 (Unknown, Bob Shaw, Dennis Dobson, ISBN-10: 0234771224, £3.50, 255 pages, Hardcover, Anthology)