For Your Information: The Demotion of Pluto

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Overview:

Title: For Your Information: The Demotion of Pluto
Author: Willy Ley
Year: 1956
Type: Essays
Series: For Your Information

Variant Titles:

1959. Die Suche nach dem Planeten X

Editions/Publications:

Unknown. Galaxy Science Fiction, August 1956 (Unknown, Willy Ley, Galaxy Publishing Corporation, $0.35, 148 pages, digest, MAGAZINE)