Region
United States
36
China
4
Asia, Eastern
2
Brazil
2
France
2
Great Britain
2
Africa
1
Argentina
1
Arizona
1
Chile
1
Colorado
1
Communist countries
1
Costa Rica
1
Developing countries
1
East Asia
1
England
1
Europe
1
Europe, Eastern
1
European Union countries
1
Germany
1
Greece
1
Guatemala
1
Iowa
1
Italy
1
Japan
1
Latin America
1
Lower Rio Grande Valley
1
Minnesota
1
Peru
1
Russia (Federation)
1
Southeast Asia
1
Southern States
1
Soviet Union
1
Taiwan
1
Texas
1
Utah
1