Letter (Astounding Stories, June 1937): Centrifugal Force.

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Overview:

Title: Letter (Astounding Stories, June 1937): Centrifugal Force.
Author: Willy Ley
Year: 1937
Type: Essays
Series: Letters: Willy Ley

Variant Titles:

1937. Letter (Astounding Stories, June 1937): Centrifugal Force.