Kula, E. (1994). Economics of Natural Resources, the Environment and Policies (2nd. ed.). chapman & hall.
Chicago-viite (17. p.)Kula, E. Economics of Natural Resources, the Environment and Policies. 2nd. ed. London: chapman & hall, 1994.
MLA-viite (9. p.)Kula, E. Economics of Natural Resources, the Environment and Policies. 2nd. ed. chapman & hall, 1994.
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