Blue Book, April 1939

From Author Wars - https://authorwars.com/publications/blue-book-april-1939-400163.html

Overview:

Title: Blue Book, April 1939
Author: Editors of The Blue Book Magazine
Year: 1939
Publisher: McCall Corporation
Price: $0.15
Pages: 144
Binding: pulp
Type: MAGAZINE
Title Reference: The Cave of the Invisible
Notes: v68 #6