| year of publication | ISBN | author(s) | title |
|---|---|---|---|
| 1999 | 978-1-902851-00-6 | Richard Humberstone | Estonian Air Force, 1918-40 (Insignia Air Force Special S.) |
| '' | 978-1-902851-01-3 | Richard Humberstone | Lithuanian Air Force, 1918-40 (Insignia Air Force Special S.) |
| 2000 | 978-1-902851-04-4 | '' | Latvian Air Force, 1918-40 (Insignia Air Force Special S.) |