Letter (Astounding Stories of Super-Science, July 1930)
| First published | July 1930 |
|---|---|
| Type | Essay |
| Date | Publication | Publisher | Type | Page | |
|---|---|---|---|---|---|
| July 1930 |
|
Astounding Stories of Super-Science, July 1930 | Publishers' Fiscal Corp | MAGAZINE | 136|136.1 |
| June 2009 | Astounding Stories of Super-Science, July 1930 | Project Gutenberg | Anthology | ||
| May 2014 |
|
Astounding Stories of Super-Science, July 1930 | LibriVox | Anthology | |8.2 |