Kula, E. (1992). Economics of natural resources and the environment. Chapman & Hall.
Chicago Style aipamenaKula, Erhun. Economics of Natural Resources and the Environment. London: Chapman & Hall, 1992.
MLA aipamenaKula, Erhun. Economics of Natural Resources and the Environment. Chapman & Hall, 1992.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.