APA (7th ed.) Citation

National Geographic Society (U.S.) & Thomas, T. Οι αρκούδες: The grizzlies. National Geographic Society.

Chicago Style (17th ed.) Citation

National Geographic Society (U.S.) and Theodore Thomas. Οι αρκούδες: The Grizzlies. [Washington D.C.] : Αθήνα: National Geographic Society.

MLA (9th ed.) Citation

National Geographic Society (U.S.) and Theodore Thomas. Οι αρκούδες: The Grizzlies. National Geographic Society.