Region
United States
138
Soviet Union
9
Asia
6
Developing countries
6
Southern States
5
Great Britain
4
Hungary
4
Communist countries
3
Nicaragua
3
Vietnam
3
Washington (D.C.)
3
Europe
2
Europe, Eastern
2
Middle East
2
South Africa
2
Afghanistan
1
Australia
1
Canada
1
Caribbean Area
1
China
1
Connecticut
1
Czechoslovakia
1
East Asia
1
India
1
Israel
1
Japan
1
Latin America
1
New York (State)
1
Pacific Area
1
Poland
1
Southeast Asia
1
Texas
1
Tibet Autonomous Region (China)
1
Zimbabwe
1