The Caves of Karst

From Author Wars - https://authorwars.com/publications/the-caves-of-karst-563766.html

Overview:

Title: The Caves of Karst
Author: Lee Hoffman
Year: 1969
Publisher: Ballantine Books
Price: C$0.75
Pages: 224
Binding: Paperback
Type: Novel
Title Reference: The Caves of Karst
Notes:
• "First printing: March 1969"; no number line • The artist is not credited, there is a very faint signature on the artwork which seems to end with Ray • Cover printed in the US, book in Canada