| Date | Publication | Publisher | Type | Page | |
|---|---|---|---|---|---|
| November 1968 |
|
Analog Science Fiction -> Science Fact, November 1968 | Condé Nast | MAGAZINE | 8 |
| July 2009 |
|
A Sense of Infinity | Baen Books | Collection | 417 |
| July 2009 |
|
A Sense of Infinity | Baen Books | Collection |