Daugherty, Carrol R.
The labor problems of American society
Houghton Mifflin, 1952
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Quint, Howard H
Main problems in American history
Dorsey Press, 1968
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Mansfield, Edwin
Economic problems : principles, problems, decisions
W.W. Norton, 1974
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Meade, James E.
Problems of economic union
University of Chicago Press, 1953
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Kiekhofer, William H.
Economic principles, problems, and policies
D. Appleton Century, 1946
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