Allen, Shirley Walter
Conserving natural resources principles and practice in a democracy
McGraw-Hill, 1959
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Burke, Mary A.
Organization of multimedia resources: principles and practice of information retrieval
Gower , 2001
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Catt, Helena
Democracy in practice
Routledge , 1999
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Le Boutillier, Cornelia Geer
American democracy and natural law
Columbia University Press, 1950
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Pearce, David William, 1941-
Economics of natural resources and the environment
Harvester Wheatsheaf, 1990
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