Krutilla, J. V. (1972). Natural environents: Studies in theoretical and applied analysis. Resources for the Future by Johns Hopkins Press University Press.
Chicago-viite (17. p.)Krutilla, John V. Natural Environents: Studies in Theoretical and Applied Analysis. Baltimore: Resources for the Future by Johns Hopkins Press University Press, 1972.
MLA-viite (9. p.)Krutilla, John V. Natural Environents: Studies in Theoretical and Applied Analysis. Resources for the Future by Johns Hopkins Press University Press, 1972.
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