Region
Europe --
17
Europe
10
United States --
5
United States
4
Soviet Union
3
Soviet Union --
3
Arabs
1
Arabs --
1
Asia
1
Asia --
1
Asia, Southeastern
1
Asia, Southeastern --
1
Canada --
1
Developing countries
1
France
1
France --
1
Germany
1
Germany (West)
1
Germany (West) --
1
Germany --
1
India
1
India --
1
Russia (Federation)
1
Russia (Federation) --
1