Geographic Subject
United States
Soviet Union
11
Middle East
9
Turkey
6
Latin America
5
China
4
Cuba
4
Europe
4
Germany
4
Greece
4
Iran
4
Japan
4
Nicaragua
4
North Carolina
4
Pennsylvania
4
Saudi Arabia
4
Alabama
3
Caribbean Area
3
France
3
Israel
3
Liberia
3
New York (State)
3
Panama
3
Yugoslavia
3
Africa, Southern
2
Alaska
2
Arkansas
2
Bermuda Islands
2
Brazil
2
Colombia
2
Communist countries
2
Egypt
2
Ethiopia
2
Georgia
2
Haiti
2
Honduras
2
Hungary
2
India
2
Indian Ocean Region
2
Ireland
2
Kentucky
2
Korea
2
Latvia
2
Madagascar
2
Mexico
2
Philippines
2
Romania
2
Tennessee
2
Texas
2
Algeria
1
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