Geography
United States
38 results
Great Britain
15 results
Confederate States of America
5 results
England
5 results
Texas
3 results
China
2 results
Maine
2 results
Connecticut
1 results
Developing countries
1 results
India
1 results
Japan
1 results
Massachusetts
1 results
Netherlands
1 results
Nigeria
1 results
Pennsylvania
1 results
Penobscot River Watershed
1 results
Rhode Island
1 results
Taiwan
1 results