Region
Soviet Union
Soviet Union --
166
United States --
66
United States
63
China
26
China --
23
Asia
13
Asia --
12
Developing countries
10
Europe --
9
Europe, Eastern
9
Europe, Eastern --
9
Europe
7
Middle East
7
Middle East --
7
Asia, Southeastern
6
Asia, Southeastern --
6
India
6
India --
6
Japan --
6
East Asia --
5
Japan
5
Pacific Area
5
Afghanistan --
4
Developing countries --
4
East Asia
4
Pacific Area --
4
Russia (Federation)
4
Russia (Federation) --
4
Great Britain
3
Great Britain --
3
Israel
3
Israel --
3
Pakistan
3
Pakistan --
3
Russia
3
Syria
3
Syria --
3
Yugoslavia
3
Yugoslavia --
3
Afghanistan
2
Africa
2
Africa --
2
Eastern Europe
2
Germany
2
Germany --
2
Russia --
2
Singapore
2
Singapore --
2
South Asia
2
more ...