Subject Region
United States
51
China
14
Japan
10
Germany
8
Europe
7
Great Britain
6
Korea (South)
5
Soviet Union
5
Spain
5
Argentina
4
Asia
4
Mexico
4
Communist countries
3
East Asia
3
Pakistan
3
Canada
2
Germany (West)
2
Hungary
2
India
2
Korea
2
Russia
2
Southeast Asia
2
Brasil
1
Brazil
1
Catalonia
1
Chile
1
Developing countries
1
Ecuador
1
Espana
1
Europe, Eastern
1
Former Soviet republics
1
France
1
Italy
1
Korea (North)
1
Macau (China : Special Administrative Region)
1
Macau (Special Administrative Region)
1
Minnesota
1
Netherlands
1
Pacific Ocean
1
Québec (Province)
1
Yugoslavia
1