Introduction: When the Future Meets the Past (Twice in Time)
| First published | November 1988 |
|---|---|
| Type | Essay |
| Date | Publication | Publisher | Type | Page | |
|---|---|---|---|---|---|
| November 1988 |
|
Twice in Time | Baen Books | Collection | 1 |
| November 1988 |
|
Twice in Time | Baen Books | Collection | 1 |
| September 2015 |
|
Twice in Time | Baen Books | Collection | |1 |