Geographic Subject
Germany
109
Sweden
67
France
57
Switzerland
48
Denmark
32
Netherlands
31
Russia (Pre-1917)
30
Finland
20
Russia (Federation)
18
Germany (West)
10
Indonesia
10
University of Bergen (Norway)
10
United States
8
Great Britain
7
Munich
7
Basel
6
Estonia
6
Paris
6
Saint Petersburg
6
Soviet Union
6
Austria
5
Copenhagen
5
Europe
5
Greenland
5
Italy
5
Zurich
5
Bavaria
4
China
4
England
4
Ethiopia
4
Russia
4
Spain
4
Suède
4
4.070
3
4.415
3
Africa
3
Berlin
3
Bern
3
Brittany
3
Czech Republic
3
Developing countries
3
Egypt
3
Greece
3
Guatemala
3
Hamburg
3
Indochina
3
Kenya
3
Moscow
3
Tunisia
3
Ukraine
3
more ...