Wordcount (Gutenberg): 9899 words
| Date | Publication | Publisher | Type | Page | |
|---|---|---|---|---|---|
| June 1960 |
|
Astounding/Analog Science Fact & Fiction, June 1960 | Street & Smith Publications, Inc. | MAGAZINE | 43 |
| October 1960 |
|
Astounding/Analog Science Fact & Fiction, October 1960 | Atlas Publishing and Distribution Co. Ltd | MAGAZINE | 35 |
| March 1968 |
|
Impossible? | Belmont Books | Collection | 11 |
| March 1968 |
|
Impossible? | Belmont Books | Collection | 11 |
| December 2007 | Charley de Milo | Project Gutenberg | Chapbook |