Map of the battle field of Gettysburg, July 1st, 2nd, 3rd 1863.
MLA
Bachelder, John B. (John Badger), 1825-1894. Map of the battle field of Gettysburg, July 1st, 2nd, 3rd 1863.. BRBL_00502. 1883. https://collections.library.yale.edu/catalog/15811159.
APA, 6th edition
Bachelder, John B. (John Badger), 1825-1894. (["BRBL_00502"])(1883)[Map of the battle field of Gettysburg, July 1st, 2nd, 3rd 1863.]. https://collections.library.yale.edu/catalog/15811159.