Geographic Subject
Soviet Union
87
United States
18
Europe
5
China
3
Asia
2
Communist countries
2
Europe, Eastern
2
Germany (East)
2
India
2
Scandinavia
2
Vietnam
2
Africa, Sub-Saharan
1
Arab countries
1
Asia, Central
1
Cuba
1
Developing countries
1
Ethiopia
1
Europe, Central
1
Hungary
1
Indochina
1
Japan
1
Kazakhstan
1
Middle East
1
Norway
1
Red Sea Region
1