MLA

Dellenbaugh, Frederick Samuel, 1853-1935. Portraits. Box 3, folder 86. n.d.. https://collections.library.yale.edu/catalog/2018227.

APA, 6th edition

Dellenbaugh, Frederick Samuel, 1853-1935. (["Box 3, folder 86"])(n.d.)[Portraits]. https://collections.library.yale.edu/catalog/2018227.