APA aipamena

UNEP. (1997). Global environment out look. Oxford university press.

Chicago Style aipamena

UNEP. Global Environment Out Look. NewYork: Oxford university press, 1997.

MLA aipamena

UNEP. Global Environment Out Look. Oxford university press, 1997.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.