APA (7th ed.) Zitazioa
Grosvenor, M. B. National geographic: June 1972. National Geographic Society.
Chicago Style (17th ed.) Zitazioa
Grosvenor, Melville Bell. National Geographic: June 1972. Washington, EUA: National Geographic Society.
MLA (9th ed.) Zitazioa
Grosvenor, Melville Bell. National Geographic: June 1972. National Geographic Society.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.