MLA

Koch, Frederick R. (Frederick Robinson). Wyatt, Mary Nicholl. Box 25, folder 545. 1863-81. https://collections.library.yale.edu/catalog/10033898.

APA, 6th edition

Koch, Frederick R. (Frederick Robinson). (["Box 25, folder 545"])(1863-81)[Wyatt, Mary Nicholl]. https://collections.library.yale.edu/catalog/10033898.