APA (7th ed.) Zitazioa
World Health Organization. (2019). World report on vision. World Health Organization.
Chicago Style (17th ed.) Zitazioa
World Health Organization. World Report on Vision. Ginebra: World Health Organization, 2019.
MLA (9th ed.) Zitazioa
World Health Organization. World Report on Vision. World Health Organization, 2019.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.