Fifth Planet

From Author Wars - https://authorwars.com/publications/fifth-planet-265651.html

Overview:

Title: Fifth Planet
Author: Geoffrey Hoyle, Fred Hoyle
Year: Unknown
Publisher: Fawcett Gold Medal
Price: $0.95
Pages: 192
Binding: Paperback
Type: Novel
Title Reference: Fifth Planet
Notes: No printing or edition stated.
Book has a numbering oddity (mixed pagination) page 9 is the first Arabic number used. Contents is on unnumbered page. Pages 5-7 are numbered in Roman numerals.
Cover artist is not credited. No visible signature.