MLA

Dellenbaugh, Frederick Samuel, 1853-1935. Boston and California Company. Box 4, folder 130. n.d.. https://collections.library.yale.edu/catalog/2019094.

APA, 6th edition

Dellenbaugh, Frederick Samuel, 1853-1935. (["Box 4, folder 130"])(n.d.)[Boston and California Company]. https://collections.library.yale.edu/catalog/2019094.