Subject Region
United States
Canada
7
Latin America
4
England
3
Argentina
2
Europe
2
Great Britain
2
Iowa
2
Minnesota
2
Pacific States
2
Pennsylvania
2
Pittsburgh
2
South Africa
2
Washington (D.C.)
2
West (U.S.)
2
Alabama
1
Atlanta (Ga.)
1
Baltimore
1
Bismarck
1
Califorinia
1
California, Southern
1
Caribbean Area
1
Chapel Hill
1
Connecticut
1
Ireland
1
Japan
1
Maryland
1
Mexico
1
New Jersey
1
North America
1
North Carolina
1
North Dakota
1
Soviet Union
1
Spain
1
Tennessee
1
Tokyo
1
Virginia
1