Geographic Subject
Germany
519
France
219
Switzerland
214
Sweden
140
Germany (West)
137
Netherlands
68
United States
52
Soviet Union
43
Great Britain
39
Europe
37
Russia (Federation)
25
4.415
17
Japan
16
Romania
16
China
15
Finland
15
Turkey
15
India
14
Italy
14
Korea (South)
14
Algeria
13
Brazil
13
4.050
12
Iran
12
Mexico
12
Cologne
11
Morocco
11
Belgium
10
Bulgaria
10
Colombia
10
Denmark
10
Hungary
10
Indonesia
9
Nigeria
9
Poland
9
Saxony
9
Berlin
8
England
8
Spain
8
Basel
7
Bavaria
7
Developing countries
7
European Economic Community countries
7
Prussia
7
4.210
6
Austria
6
Egypt
6
Korea
6
Russia
6
Suisse
6
more ...