Subject Region
United States
Great Britain
73
Canada
41
European Union countries
41
California
28
Washington (D.C.)
26
Europe
24
New York (State)
21
Southern States
21
Germany
18
Pennsylvania
17
Massachusetts
14
New York
11
Louisiana
10
Michigan
10
Australia
9
France
9
Mexico
8
America
7
England
7
Netherlands
7
Oregon
7
European Economic Community countries
6
Georgia
6
Illinois
6
India
6
Missouri
6
South Carolina
6
Belgium
5
Estados Unidos
5
Iowa
5
Maryland
5
Mississippi
5
New Jersey
5
Virginia
5
Africa
4
Ann Arbor
4
Atlanta
4
Chicago
4
China
4
Colorado
4
Connecticut
4
Cuba
4
Hudson River (N.Y. and N.J.)
4
Italy
4
Los Angeles
4
Middle East
4
North America
4
North Carolina
4
Rhode Island
4
more ...