Leftwich, Richard H., author
a Basic framework for economics / Richard H. Leftwich
Business Publishing , 1984
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Leftwich, Richard H., author
Economics of social issues/ Richard H. Leftwich, Ansel M. Sharp
Business Publications,Inc., 1974
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Leftwich, Richard H., author
Study guide to accompany economics of sosial issues/ Richard H. Leftwich
United States of America, 1984
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Heyne, Paul
The economic way of thinking / Paul Heyne
Prentice-Hall, 2000
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Heyne, Paul T.
The Economic way of thinking / Paul T. Heyne
Science Research Associates, 1973
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