MLA

Dellenbaugh, Frederick Samuel, 1853-1935. Utah. Box 3, folder 104. 1920 Oct. https://collections.library.yale.edu/catalog/2018306.

APA, 6th edition

Dellenbaugh, Frederick Samuel, 1853-1935. (["Box 3, folder 104"])(1920 Oct)[Utah]. https://collections.library.yale.edu/catalog/2018306.