Twenty Questions: A Classification of Cosmic Civilization
From Author Wars - https://authorwars.com/books/twenty-questions-a-classification-of-cosmic-civilization-1534340.html
Overview:
- Title: Twenty Questions: A Classification of Cosmic Civilization
- Author: Carl Sagan
- Year: 1973
- Type: Essays
Editions/Publications:
- Unknown. The Cosmic Connection: An Extraterrestrial Perspective (Unknown, Carl Sagan, Anchor Press / Doubleday, ISBN-10: 0385004575, $7.95, xiii+274 pages, Hardcover, Non-fiction)
- Unknown. The Cosmic Connection: An Extraterrestrial Perspective (Unknown, Carl Sagan, Coronet, ISBN-10: 0340196823, £0.85, xiii+274 pages, Trade Paperback, Non-fiction)