Novelet. Illustrated by Virgil Finlay. Appeared in the anthology [i]Worlds Apart: An Anthology of Science Fiction[/i] edited by Amabel Williams-Ellis and Mably Owen, published in 1966.

Novelet. Illustrated by Harry Rosenbaum. Story aired on the radio program [i]X Minus One[/i] in 1956.

Article.

Short story. Illustrations by Timmins. Appeared in the anthologies [i]Possible Worlds of Science Fiction[/i], Groff Conklin, ed. (1951); [i]Stories of Scientific Imagination[/i], Joseph Gallant, ed. (1954); [i]Great Stories of Space Travel[/i], Groff Conklin, ed. (1963).

Novelet. Illustrated by mel Hunter. Story aired on the radio program [i]X Minus One[/i] in 1956. Available as a free ebook on Project Gutenberg.

Novelette. Illustrated by Freas. Part of the Colonial Survey Series. A free ebook is available on Project Gutenberg.

Short story. Illustrated by Frees. Available as a free audio book on LibriVox. Available on Project Gutenberg as a free ebook.

Short story. Illustrated by Freas.

Serial: part 1 of 2 parts. Illustrated by John Schoenherr. Story expanded into the nove [i]The Other Side of Nowhere[/i] (1964).

Short story. Illustrations by A. Williams. Appeared in the collected works [i]The Best of Murray Leinster[/i] (1976) and [i]First Contacts: The Essential Murray Leinster [/i](1998). Appeared in the anthologies [i]A Treasury of Science Fiction[/i], Groff Conklin, ed. (1948); [i]Giants Unleashed[/i], Groff Conklin, ed. (1965); [i]Minds Unleashed[/i], Groff Conklin, ed. (1970).