Region
Africa
4
America
1
Argentina
1
Asia
1
Cambridge
1
Canada
1
Caribbean Area
1
China
2
Developing countries
1
English-speaking countries
1
Europe
8
Foreign countries
1
France
3
Germany
2
Great Britain
2
India
1
Italy
1
Japan
1
Korea
1
Latin America
4
Marshall (Minn.)
1
Massachusetts
1
Minnesota
1
New Caledonia
1
Russia
1
Russia (Federation)
1
Saint Vincent and the Grenadines
1
Southern States
3
Soviet Union
1
Spain
3
United States
39
West (U.S.)
1