Those Who Watch

From Author Wars - https://authorwars.com/publications/those-who-watch-274233.html

Overview:

Title: Those Who Watch
Author: Robert Silverberg
Year: Unknown
ISBN-10: 0451081498
Publisher: Signet / New American Library of Canada
Price: C$1.50
Pages: 143
Binding: Paperback
Type: Novel
Title Reference: Those Who Watch
Notes:
• "First Signet Printing, April, 1967"
• Sixth printing by the number line 6789
• The artist is not credited, szafran is on the cover.
• Cover printed in the US, book in Canada