Our Man in Space / Ultimatum in 2050 A.D.

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Overview:

Title: Our Man in Space / Ultimatum in 2050 A.D.
Author: Bruce W. Ronald, Jack Sharkey
Year: 1965
Publisher: Ace Books
Price: $0.45
Pages: 131+120
Binding: dos
Type: Omnibus
Title Reference: Our Man in Space / Ultimatum in 2050 A.D.
Notes:
- Cover for Our Man in Space states "Complete Novel"
  - Cover is credited to Ed Valigursky on the copyright page, no visible signature
  - Our Man in Space is 131 pages, ©1965
- Cover for Ultimatum in 2050 A.D. states "First Book Publication"
  - Cover art is credited to John Schoenherr on the copyright page, no visible signature
  - Ultimatum in 2050 A.D. is 120 pages, ©1965
- Page 5 of both titles have interior art signed by Jack Gaughan, neither piece is credited