MLA
Colton's Map of the State of Georgia. G.W. & C.B. Colton, 1866. Emory University. General Libraries. https://digital.library.emory.edu/purl/972p5hqgq0-cor.
APA, 6th edition
Colton's map of the state of Georgia. (1866). G.W. & C.B. Colton; Emory University. General Libraries. https://digital.library.emory.edu/purl/972p5hqgq0-cor.
Chicago
“Colton's Map of the State of Georgia.” Stuart A. Rose Manuscripts, Archives, and Rare Books Library Digitized Books Collection. New York: G.W. & C.B. Colton, 1866. Emory University. General Libraries. https://digital.library.emory.edu/purl/972p5hqgq0-cor.