Cite

Military map of the United States / compiled and drawn by E. Freyhold.

MLA

Freyhold, Edward. Military Map of the United States / Compiled and Drawn by E. Freyhold. Office of the Chief of Engineers, War Department, 1870. https://collections.library.yale.edu/catalog/15536527.

APA, 6th edition

Freyhold, E. (1870). Military map of the United States / compiled and drawn by E. Freyhold. [Maps]. Office of the Chief of Engineers, War Department, https://collections.library.yale.edu/catalog/15536527.