Region
Soviet Union --
241
Soviet Union
170
United States --
71
United States
67
China --
25
China
24
Asia
14
Asia --
12
Developing countries
10
Europe, Eastern
10
Europe, Eastern --
10
Europe --
9
Middle East
9
Middle East --
9
Europe
8
India
8
India --
8
Russia (Federation) --
7
Asia, Southeastern
6
Asia, Southeastern --
6
East Asia --
5
Japan
5
Pacific Area
5
Developing countries --
4
East Asia
4
Japan --
4
Pacific Area --
4
Russia (Federation)
4
Great Britain
3
Great Britain --
3
Israel
3
Israel --
3
Russia
3
Russia --
3
Soviet Union - --
3
Syria
3
Syria --
3
United states --
3
Yugoslavia
3
Yugoslavia --
3
Afghanistan --
2
Africa
2
Africa --
2
Eastern Europe
2
Germany
2
Germany --
2
Pakistan
2
Pakistan --
2
Singapore
2
Singapore --
2
more ...