Cite

Map of the seat of war, showing the battles of July 18th, 21st & Oct. 21st, 1861.

MLA

Corbett, V. P. Map of the Seat of War, Showing the Battles of July 18th, 21st & Oct. 21st, 1861. V.P. Corbett, 0AD. https://collections.library.yale.edu/catalog/15811287.

APA, 6th edition

Corbett, V. P. (0 C.E.). Map of the seat of war, showing the battles of July 18th, 21st & Oct. 21st, 1861. [Maps]. V.P. Corbett, https://collections.library.yale.edu/catalog/15811287.