National Geographic Society (U.S.), Dunn, J. L., & Alderfer, J. K. (2011). National Geographic field guide to the birds of North America (Sixth edition.). National Geographic Society.
Style de citation Chicago (17e éd.)National Geographic Society (U.S.), Jon L. Dunn, et Jonathan K. Alderfer. National Geographic Field Guide to the Birds of North America. Sixth edition. Washington, D.C.: National Geographic Society, 2011.
Style de citation MLA (8e éd.)National Geographic Society (U.S.), et al. National Geographic Field Guide to the Birds of North America. Sixth edition. National Geographic Society, 2011.
Attention : ces citations peuvent ne pas être correctes à 100%.