Hidden Variables

From Author Wars - https://authorwars.com/publications/hidden-variables-17012.html

Overview:

Title: Hidden Variables
Author: Charles Sheffield
Year: 1981
ISBN-10: 0441329918
Publisher: Ace Books
Price: $2.75
Pages: viii+359
Binding: Paperback
Type: Collection
Title Reference: Hidden Variables
Notes:
• "First Ace Printing: July 1981" • Full number line: 2 4 6 8 0 9 7 5 3 1 • The artist is not credited, no visible signature • Each story has a titled Afterword.