Region
United States
42
Guatemala
4
Mali
3
Bandiagara Caves (Mali)
2
Brazil
2
Niger River Valley
2
Paraguay
2
Algeria
1
Azerbaijan
1
Belize
1
Bolivia
1
Costa Rica
1
Dominican Republic
1
Ecuador
1
European Economic Community countries
1
Gabon
1
Georgia (Republic)
1
Great Britain
1
Greece
1
India
1
Ireland
1
Kenya
1
Kuwait
1
Libya
1
Malaysia
1
Maldives
1
Mauritius
1
Mexico
1
Moldova
1
Morocco
1
Netherlands
1
Pakistan
1
Senegal
1
Singapore
1
Trinidad and Tobago
1
Ukraine
1
Uruguay
1
Vietnam
1