Huck and Yogi Jamboree #Z101

On sale date is Library of Congress copyright record publication date.

Unusual format Dell squarebound; part color cover, black and white interiors. (c) Copyright 1961 by Hanna-Barbera Productions; first printing March 1961

Has a companion, see: The Flintstones on the Rocks (Dell, 1961 series) #Z102

In similar format, see also: Beetle Bailey and Sarge (Dell, 1958 series) #SB-Z4

Could be considered an early Graphic Novel, as it is comics material created to be published in a book format (not originally printed in a magazine or newspaper strip).