Humphrey, John
Contemporary problems in the conflict of laws
A.W. Sijthoff, 1978
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Green, Arnold W.
Social problems: arena of conflict
McGraw-Hill, 1975
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Little, A. W. Selwyn
American economic problems
The United States Armed Forces Institute, 1941
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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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