National Geographic Television, Willumsen, G., & Kiley, R. (2009). 30 years of National Geographic specials. National Geographic.
Style de citation Chicago (17e éd.)National Geographic Television, Gail Willumsen, et Richard Kiley. 30 Years of National Geographic Specials. [Washington, D.C.]: National Geographic, 2009.
Style de citation MLA (8e éd.)National Geographic Television, et al. 30 Years of National Geographic Specials. National Geographic, 2009.
Attention : ces citations peuvent ne pas être correctes à 100%.