Geographic Subject
Germany
166
France
72
Switzerland
61
Sweden
59
Netherlands
47
Indonesia
22
Iran
22
China
20
Turkey
20
Germany (West)
19
India
19
Europe
16
Poland
16
United States
16
Egypt
15
Morocco
15
Brazil
14
Developing countries
13
Great Britain
13
Romania
12
Denmark
11
Greece
11
Italy
11
Japan
11
Kenya
11
Bulgaria
10
Finland
10
Mexico
10
Africa
9
South Africa
9
4.050
8
Austria
8
Senegal
8
Spain
8
Africa, West
7
Soviet Union
7
Tanzania
7
Thailand
7
Africa, East
6
Algeria
6
Bavaria (Germany)
6
Burkina Faso
6
Congo (Brazzaville)
6
Congo (Democratic Republic)
6
England
6
Israel
6
Java (Indonesia)
6
Korea (South)
6
Middle East
6
Namibia
6
more ...