Short story. Illustrated by David Maus.

Short story. Illustrated by George Schelling. Part of the Depression or Bust series. Available as a free e-book on Project Gutenberg. Appeared in the anthology [i]The Science Fiction Megapack: 25 Science Fiction Stories by Masters[/i], edited by John Gregory Betancourt, published in 2011.

Novelet. Illustrated by Ritter. Appeared in the anthology [i]Worlds of When[/i], edited by Groff Conklin, published in 1962.

Serial: part 1 of 2 parts. Illustrated by John Schoenherr. Story was expanded and published as a novel in 1963 under the title "The Earth War." Story is available as a free ebook on Project Gutenberg.

Novelette. Illustrated by John Schoenherr. Appeared in the anthologies [i]Analog 4[/i], edited by John W. Campbell, published in 1966; and [i]The Permanent Implosion[/i], edited by John W. Campbell, published in 1970.

Short story. Illustrated by Douglas. Appeared in the collected works [i]The Best of Mack Reynolds[/i], published in 1976 and [i]Compounded Interests[/i], published in 1983. Appeared in the anthologies [i]Analog 2[/i], edited by John W. Campbell, Jr., published in 1964 and [i]Analog Anthology[/i], edited by John W. Campbell, Jr., published in 1965.

Serial: part 1 of 3 parts. Illustrated by Robert Swanson. Part of the Joe Mauser series. Published as a novel in 1966 under the title [i]Time Gladiator[/i].

Serial: part 2 of 3 parts. Illustrated by Robert Swanson.

Short novel. Illustrated by Schoenherr. This is part 1 of the novel [i]Planetary Agent X[/i] published in 1965. Full text availalbe at Project Gutenberg. Audio book available on LibriVox.