Bulgaria
| Country: | Bulgaria |
| Type: | Postage stamps |
| Series: | Int. Airmail Exhibition, Strasbourg |
| Nominal: | 28 лв |
| Year: | 1932 |
| Perforation: | 11½ |
| Mintage: | 30,000 |
Int. Airmail Exhibition, Strasbourg
 Junkers G 31 above the Rila Monastery |  Junkers G 31 above the Rila Monastery |  Junkers G 31 above the Rila Monastery |