The Door Into Summer

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Overview:

Title: The Door Into Summer
Author: Robert A. Heinlein
Year: Unknown
Publisher: Signet
Price: $0.75
Pages: 159
Binding: Paperback
Type: Novel
Title Reference: The Door Into Summer
Notes: Stated 9th printing.
Artist not credited but the actual artwork in the lower half of the cover is the same as that of the first printing in March of 1959.