On Building Walls

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Overview:

Title: On Building Walls
Author: Baen
Year: 1974
Type: Essays

Editions/Publications:

Unknown. Worlds of If, September-October 1974 (Unknown, Baen, UPD Publishing Corporation, $0.75, 180 pages, digest, MAGAZINE)
Unknown. Worlds of If, September-October 1974 [UK] (Unknown, Baen, Universal-Tandem Publishing Company Ltd., £0.30, 180 pages, digest, MAGAZINE)