Sheets of United Nations, 1999
| Issuer | Date | Desc | State | ||
| - | no image | United Nations | 7/7/1999 | empty sheet (#32593) | incomplete |
| - |  |
United Nations | 7/7/1999 | 3rd Conference on Exploration and Peaceful Uses of Outer Space, empty sheet (#32594) | incomplete |
| - |  |
United Nations | 9/21/1999 | "In Memoriam - Fallen in the Cause of Peace", sheet of 1 type | all added |