Region
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Malaysia
8
Middle West
8
New Zealand
8
Northeastern States
8
Pacific Area
8
Taiwan
8
Vietnam
8
Alabama
7
Chicago
7
Chile
7
Cibola National Forest
7
Columbia River Watershed
7
Denver
7
East Asia
7
European Economic Community countries
7
Golden Gate National Recreation Area (Calif.)
7
Iowa
7
Kiowa National Grassland (N.M.)
7
Korea
7
Maine
7
Middle East
7
Nebraska
7
Norway
7
Peru
7
Switzerland
7
Tennessee River Valley
7
Turkey
7
United States, West
7
Yosemite National Park (Calif.)
7
Yucca Mountain
7
Atlanta
6
Central America
6
Cibola National Forest (N.M.)
6
Everglades (Fla.)
6
Foreign countries
6
Ghana
6
Great Lakes (North America)
6
McClellan Creek National Grassland (Tex.)
6
Missouri River
6
Missouri River Watershed
6
Pacific Coast (U.S.)
6
Rhode Island
6
Russia (Federation)
6
Singapore
6
Southern States
6
Syria
6
États-Unis
6
America
5
Arkansas
5
Bangladesh
5
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