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
Publisher: Ace Books
Price: $0.45
Pages: 127+129
Binding: dos
Type: Omnibus
Title Reference: Empress of Outer Space
Notes:
- Cover for The Alternate Martians has "First Book Publication"
  - The Alternate Martians 129 pages
- Cover for Empress of Outer Space has "Complete Novel"
  - Empress of Outer Space 127 pages
- Cover art for both titles is credited to Jerome Podwil.
- Page 5 of both titles have interior art signed by Jack Gaughan.