J. P. · J. S. · Jay Spenser · P S
| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| Vertical Challenge: The Hiller Aircraft Story | 978-0-295-97203-9 (0-295-97203-3) | 1992 |
| Whirlybirds: A History of the U.S. Helicopter Pioneers | 978-0-295-97699-0 (0-295-97699-3) | 1998 |
| Whirlybirds a history of the U. S. helicopter pioneers | 978-0-295-98058-4 (0-295-98058-3) | 1998 |