| Issuer | Date | Desc | State | ||
| - | |
Bulgaria | 2/10/1999 | empty sheet (#6289) | incomplete |
| - | |
Bulgaria | 3/15/1999 | empty sheet (#6292) | incomplete |
| - | |
Bulgaria | 4/15/1999 | empty sheet (#6290) | incomplete |
| - | no image | Bulgaria | 6/15/1999 | empty sheet (#6293) | incomplete |
| - | no image | Bulgaria | 7/20/1999 | empty sheet (#6294) | incomplete |
| - | no image | Bulgaria | 7/27/1999 | empty sheet (#6291) | incomplete |
| - | |
Bulgaria | 8/10/1999 | empty sheet (#6295) | incomplete |
| - | no image | Bulgaria | 10/5/1999 | empty sheet (#6296) | incomplete |