Perman, R., Ma, Y., Common, M., Maddison, D., & McGlivray, J. (2011). Natural resource and environmental economics (Forth edition.). Pearson Addison Wesley.
Lua i Stíl Chicago (17ú heag.)Perman, Roger, Yue Ma, Michael Common, David Maddison, agus James McGlivray. Natural Resource and Environmental Economics. Forth edition. Harlow, Essex ; New York: Pearson Addison Wesley, 2011.
Lua MLA (8ú heag.)Perman, Roger, et al. Natural Resource and Environmental Economics. Forth edition. Pearson Addison Wesley, 2011.
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