Allamagoosa by Eric Frank Russell. © 1955 by Street & Smith Publications, Inc. Appeared originally in Astounding Science Fiction, May 1955.

The Darfsteller by Walter M. Miller, Jr. © 1955 by Street & Smith Publications, Inc. Appeared originally in Astounding Science Fiction, January 1955.

The Star by Arthur C. Clarke, © 1955 by Royal Publications, Inc. Appeared originally in Infinity Science Fiction, November 1955.

Exploration Team by Murray Leinster, © 1956 by Street & Smith Publications, Inc. Appeared originally in Astounding Science Fiction, March 1956.

© 1962 by Isaac Asimov.

Ed. cast.: © 1972 by Ediciones Dronte. Published by arrangement with Doubleday & Company, Inc.