The Ultimate Enemy

From Author Wars - https://authorwars.com/publications/the-ultimate-enemy-49008.html

Overview:

Title: The Ultimate Enemy
Author: Fred Saberhagen
Year: 1979
ISBN-10: 0441843158
Publisher: Ace Books
Price: $1.95
Pages: 242
Binding: Paperback
Type: Collection
Title Reference: The Ultimate Enemy
Notes:
• "First Ace printing: September 1979" • Full number line 2468097531 • Cover art is credited to Whelan on the copyright page; no visible signature • Back cover states "First Book Publication"