Winpenny, J. T. (1991). Values for the environment: A guide to economic appraisal. Overseas Development Inst..
Dyfyniad Arddull ChicagoWinpenny, James T. Values for the Environment: A Guide to Economic Appraisal. London: Overseas Development Inst., 1991.
Dyfyniad MLAWinpenny, James T. Values for the Environment: A Guide to Economic Appraisal. Overseas Development Inst., 1991.
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