The Alternate Martians / Empress of Outer Space

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Overview:

Title: The Alternate Martians / Empress of Outer Space
Author: A. Bertram Chandler
Year: 1965
Type: Omnibuses

Editions/Publications:

Unknown. The Alternate Martians / Empress of Outer Space (Unknown, A. Bertram Chandler, Ace Books, $0.45, 127+129 pages, dos, Omnibus)