The Caves of Mars / Space Mercenaries

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Overview:

Title: The Caves of Mars / Space Mercenaries
Author: Emil Petaja, A. Bertram Chandler
Year: 1965
Publisher: Ace Books
Price: $0.45
Pages: 125+131
Binding: dos
Type: Omnibus
Title Reference: Space Mercenaries
Notes:
- Cover for The Caves of Mars has "First Book Publication"
  - Cover artist is uncredited and signature is not visible on the artwork. ACE Image Library credits Alex Schomburg.
  - The Caves of Mars 125 pages
- Cover for Space Mercenaries has "Complete Novel"
  - Artist's signature on the artwork "Gray Morrow"
  - Space Mercenaries 131 pages
- Page 5 of both titles have interior art signed by Jack Gaughan.
- For individual, clear images, see here for Space Mercenaries and here for The Caves of Mars.