Region
United States --
34
United States
33
Soviet Union --
9
Developing countries
5
East Asia --
5
Iran --
5
Japan
5
Europe --
4
Iran
4
Japan --
4
Soviet Union
4
China --
3
Estonia
3
Germany --
3
Indonesia
3
Indonesia --
3
Latvia --
3
Pacific Area --
3
Africa, Sub-Saharan --
2
Asia, Central
2
Asia, Southeastern --
2
Azerbaijan --
2
China
2
Developing countries --
2
East Asia
2
Estonia --
2
Europe
2
Former Soviet republics --
2
France
2
France --
2
Germany
2
Latin America --
2
Latvia
2
Mongolia --
2
Russia
2
Russia (Federation) --
2
Sudan --
2
Thailand --
2
Africa
1
Africa --
1
Africa, West
1
African, Sub-Saharan
1
Albania --
1
Armenia (Republic) --
1
Asia
1
Asia --
1
Asia, Central --
1
Asia, Southeastern
1
Azerbaijan
1
Belarus
1
more ...