APA (7th ed.) Citation

National Geographic Society (U.S.). (2013). Railroad legacy map of the United States. National Geographic Society.

Chicago Style (17th ed.) Citation

National Geographic Society (U.S.). Railroad Legacy Map of the United States. Washington, D.C.: National Geographic Society, 2013.

MLA (9th ed.) Citation

National Geographic Society (U.S.). Railroad Legacy Map of the United States. National Geographic Society, 2013.

Warning: These citations may not always be 100% accurate.