Sentry of the Sky [3]
From Author Wars - https://authorwars.com/books/sentry-of-the-sky-3-961841.html
Editions/Publications:
- Unknown. Galaxy Magazine, February 1961 (Unknown, Ritter, Galaxy Publishing Corporation, $0.50, 196 pages, digest, MAGAZINE)
- Unknown. Galaxy Science Fiction [UK], No. 84 (Unknown, Ritter, Galaxy Publishing Corporation, 3/6, 198 pages, digest, MAGAZINE)
- 2016 . Sentry of the Sky (2016, Ritter, Project Gutenberg, $0.00, ebook, Chapter Book)