MLA

Dellenbaugh, Frederick Samuel, 1853-1935. Arizona. Box 1 | Folder 30. undated. https://collections.library.yale.edu/catalog/2017655.

APA, 6th edition

Dellenbaugh, Frederick Samuel, 1853-1935. (["Box 1 | Folder 30"])(undated)[Arizona]. https://collections.library.yale.edu/catalog/2017655.