Cite

[Massachusetts regiment preparing for Mexican campaign]

MLA

[Massachusetts Regiment Preparing for Mexican Campaign]. 0AD. https://collections.library.yale.edu/catalog/2017471.

APA, 6th edition

[Massachusetts regiment preparing for Mexican campaign]. (0 C.E.). [Photographic postcards, Photographic prints, Photographs]. https://collections.library.yale.edu/catalog/2017471.