International Oceanography Congresses.
90%
| Country: | Soviet Union, USSR |
|---|---|
| Issue: | International Congresses and Assemblies |
| Date: | 1966-01-01 |
| Print: | Photogravure |
| Size: | 40 x 28 |
| Perforation: | frame 11½ |
| Format: | Stamp |
| Face Value: | 6 Russian kopek |
| Print run: | 4000000 |