Cite

U.S. Soldiers arriving on the Mexican border

MLA

U.S. Soldiers Arriving on the Mexican Border. 0AD. https://collections.library.yale.edu/catalog/2017332.

APA, 6th edition

U.S. Soldiers arriving on the Mexican border. (0 C.E.). [Photographic postcards, Photographic prints, Photographs]. https://collections.library.yale.edu/catalog/2017332.