Subject Region
United States
304
Great Britain
64
Japan
63
China
54
Mexico
30
Developing countries
27
Europe
27
Canada
25
France
25
East Asia
24
India
23
European Union countries
20
Africa
19
Germany
18
Korea (South)
17
Latin America
13
Asia
10
Soviet Union
10
Europe, Eastern
9
Argentina
8
Italy
8
Brazil
7
Indonesia
7
Ireland
7
Korea
6
Taiwan
6
European Economic Community countries
5
Ontario
5
Spain
5
Africa, North
4
Austria
4
Czechoslovakia
4
Hong Kong
4
Hong Kong (China)
4
Malaysia
4
Poland
4
Sweden
4
Turkey
4
Australia
3
Czech Republic
3
Germany (West)
3
Pacific Area
3
Russia (Federation)
3
Singapore
3
South Africa
3
Southeast Asia
3
Thailand
3
Zimbabwe
3
Chile
2
Delaware
2
more ...