MLA

Hagadorn, Charles Baldwin, 1866-, Norris Peters Co. Sketch showing positions of 1st Brigade, 2nd Division, 8th Corps, in operations against Manila, P.I., August 13, 1898 / by Chas. B. Hagadorn.. BRBL_00027. [190?]. https://collections.library.yale.edu/catalog/15239169.

APA, 6th edition

Hagadorn, Charles Baldwin, 1866-, & Norris Peters Co. (["BRBL_00027"])([190?])[Sketch showing positions of 1st Brigade, 2nd Division, 8th Corps, in operations against Manila, P.I., August 13, 1898 / by Chas. B. Hagadorn.]. https://collections.library.yale.edu/catalog/15239169.