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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Mining : Natural Resources Development
Artikel Jurnal
The economics of natural resources depletion
edited by D.W. Pearce with the assistance of J. Rose
Macmillan, 1975
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