Region
Africa
3
Antarctica
1
Asia
2
Australia
5
Canada
3
Central America
1
China
4
Earth (Planet)
1
Egypt
1
England
1
Europe
3
France
1
Gettysburg National Military Park (Pa.)
1
Great Britain
6
Greece
3
India
2
Iraq
1
Israel
1
Japan
3
Kenya
1
Mars (Planet)
1
Mexico
3
Michigan
1
Netherlands
1
Nigeria
1
North America
3
Poland
1
Rome
3
Russia
2
Solar system
4
South America
1
Soviet Union
2
Study and teaching (Elementary)
1
Tennessee
3
United States
162
West (U.S.)
2
Wounded Knee (S.D.)
1
Wounded Knee Memorial and Historic Site (S.D.)
1
États-Unis
1