Subject Region
United States
99
Pennsylvania
44
Germany
17
Great Britain
14
Mexico
10
Pittsburgh
8
Bethlehem
7
Canada
7
West Virginia
7
China
6
England
6
Pittsburgh (Pa.)
6
Chicago
5
Gary
5
Homestead
5
Illinois
5
Europe
4
Homestead (Pa.)
4
Sheffield
4
Chicago (Ill.)
3
Colorado
3
Gary (W. Va.)
3
India
3
Maryland
3
Pittsburgh Region
3
Saarland
3
Sheffield (England)
3
South Chicago (Chicago, Ill.)
3
Sparrows Point
3
Braddock
2
Braddock (Pa.)
2
Duluth
2
Europe, Eastern
2
European Economic Community countries
2
France
2
Gary (Ind.)
2
Indiana
2
London
2
Magnitogorsk
2
Minnesota
2
Monongahela River Region (W. Va. and Pa.)
2
Ontario
2
Philadelphia
2
Ruhr (Region)
2
Russia (Federation)
2
Wales, South
2
Africa
1
Alabama
1
Algeria
1
Argentina
1
more ...