Quint, Howard H
Main problems in American history
Dorsey Press, 1968
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Daugherty, Carrol R.
The labor problems of American society
Houghton Mifflin, 1952
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Mansfield, Edwin
Economic problems : principles, problems, decisions
W.W. Norton, 1974
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Stigler, George J.
Five lectures on economic problems
Macmillan, 1950
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Current economic problems
Richard D. Irwin, 1972
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