APA (7th ed.) Citation

National Geographic Society (U.S.). Cartographic Division. (1952). Index to the National Geographic Society's map of North America.

Chicago Style (17th ed.) Citation

National Geographic Society (U.S.). Cartographic Division. Index to the National Geographic Society's Map of North America. Washington, D.C. : The Society, 1952.

MLA (9th ed.) Citation

National Geographic Society (U.S.). Cartographic Division. Index to the National Geographic Society's Map of North America. 1952.