Geography
United States
650 results
Texas
93 results
Canada
28 results
Developing countries
25 results
California
21 results
Great Britain
20 results
Australia
18 results
China
17 results
Florida
15 results
Mexico
15 results
Europe
14 results
Soviet Union
14 results
Oregon
12 results
Arctic regions
11 results
Galveston Bay
11 results
Galveston Bay (Tex.)
11 results
India
11 results
Mexico, Gulf of
11 results
North America
11 results
Colorado
10 results
Germany
10 results
West (U.S.)
10 results
Antarctica
9 results
Europe, Eastern
8 results
European Union countries
8 results
Great Lakes (North America)
8 results
Latin America
8 results
Mexican-American Border Region
8 results
Netherlands
8 results
Alaska
7 results
Asia
7 results
Japan
7 results
New York (State)
7 results
Washington (State)
7 results
OECD countries
6 results
Pennsylvania
6 results
Poland
6 results
Italy
5 results
New Mexico
5 results
Africa
4 results
Arizona
4 results
Brazil
4 results
Caribbean Area
4 results
Coastal Bend
4 results
Everglades
4 results
Everglades (Fla.)
4 results
Former Soviet republics
4 results
Kansas
4 results
Maryland
4 results
Mediterranean Region
4 results
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