Region
Soviet Union --
3
Europe, Eastern
2
Europe, Eastern --
2
Soviet Union
2
Africa
1
Africa --
1
Asia, Southeastern
1
Asia, Southeastern --
1
China
1
China (People's Republic of China, 1949-
1
China (People's Republic of China, 1949- ) --
1
China --
1
Former Soviet republics
1
Former Soviet republics --
1
Russia
1
Russia --
1
United States
1
United States --
1