Subject Region
United States
1,651
China
735
Developing countries
424
Great Britain
390
Latin America
252
Soviet Union
246
European Union countries
223
Europe
222
India
212
Japan
210
Argentina
197
Africa
186
Mexico
172
Europe, Eastern
161
Asia
154
Russia (Federation)
154
Germany
137
Canada
114
East Asia
112
France
94
Brazil
75
Korea (South)
62
Southeast Asia
62
America
59
Cuba
52
Chile
50
Spain
50
Peru
47
Africa, Sub-Saharan
46
European Economic Community countries
46
Middle East
46
Australia
43
South Africa
43
Indonesia
42
Greece
41
Taiwan
41
Caribbean Area
39
Ireland
39
Turkey
37
Pacific Area
36
Poland
35
America Latina
34
Italy
34
Ghana
32
Egypt
29
Vietnam
29
Europe, Central
28
Former Soviet republics
28
Hungary
28
Korea (North)
28
more ...