Geography
United States
501 results
Great Britain
46 results
Soviet Union
18 results
Texas
16 results
Developing countries
10 results
Africa
7 results
Canada
7 results
Illinois
7 results
India
7 results
China
6 results
France
6 results
Hawaii
6 results
Latin America
6 results
Maryland
6 results
Mexico
6 results
Minnesota
6 results
West (U.S.)
6 results
Appalachian Region
5 results
California
5 results
Europe
5 results
Idaho
5 results
Iowa
5 results
Louisiana
5 results
Malaysia
5 results
Montana
5 results
New Mexico
5 results
New York (State)
5 results
Wisconsin
5 results
Asia
4 results
Connecticut
4 results
Florida
4 results
Georgia
4 results
Indiana
4 results
Kentucky
4 results
Mississippi
4 results
Missouri
4 results
Peru
4 results
Russia (Federation)
4 results
Southern States
4 results
Washington (State)
4 results
Alabama
3 results
Alaska
3 results
Arizona
3 results
Arkansas
3 results
Australia
3 results
Colombia
3 results
Colorado
3 results
Delaware
3 results
England
3 results
Germany
3 results
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