USSR
Acknowledged, but not listed by SG.
| Country: | USSR |
| Type: | Postal blocks |
| Series: | World Wildlife Fund - Polar Bears |
| Nominal: | 8*10 k |
| Year: | 1987 |
| Perforation: | frame 11½ x 12 |
World Wildlife Fund - Polar Bears
 Polar Bear (Ursus maritimus) |  Polar Bear (Ursus maritimus) |  Polar Bear (Ursus maritimus) |  Polar Bear (Ursus maritimus) |