APA aipamena

Portney, P. R., & Stavins, R. N. Public policies for environmental protection (Second edition.).

Chicago Style aipamena

Portney, Paul R., and R. N. Stavins. Public Policies for Environmental Protection. Second edition.

MLA aipamena

Portney, Paul R., and R. N. Stavins. Public Policies for Environmental Protection. Second edition.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.