Map of North America: reduced from map on scale of 1:5,000,000

Chicago citation style
Geological Survey (U.S.). Map of North America: reduced from map on scale of 1:5,000,000. 1912. Retrieved from the Digital Public Library of America, http://ark.digitalcommonwealth.org/ark:/50959/7h149w69s. (Accessed July 23, 2018.)
APA citation style
Geological Survey (U.S.), (1912) Map of North America: reduced from map on scale of 1:5,000,000. Retrieved from the Digital Public Library of America, http://ark.digitalcommonwealth.org/ark:/50959/7h149w69s
MLA citation style
Geological Survey (U.S.). Retrieved from the Digital Public Library of America <http://ark.digitalcommonwealth.org/ark:/50959/7h149w69s>.
Note: These citations are programmatically generated and may be incomplete.