Perman,Roger. (1999). Natural resource and environmental economics. Longman.
Čikaški stil citiranjaPerman,Roger. Natural Resource and Environmental Economics. London: Longman, 1999.
MLA način citiranjaPerman,Roger. Natural Resource and Environmental Economics. Longman, 1999.
Upozorenje: Ovi citati možda nisu uvijek 100% točni.