Letter (Astounding, February 1939): Concerning "Gravity Plates."

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Overview:

Title: Letter (Astounding, February 1939): Concerning "Gravity Plates."
Author: Willy Ley
Year: 1939
Type: Essays
Series: Letters: Willy Ley

Editions/Publications:

Unknown. Astounding Science-Fiction, February 1939 (Unknown, Willy Ley, Street & Smith Publications, Inc., $0.20, 164 pages, pulp, MAGAZINE)