MLA

Ford, Julia Ellsworth, 1859-1950. Carman, Bliss. Box 1, folder 12. 1916 January 8. https://collections.library.yale.edu/catalog/17167809.

APA, 6th edition

Ford, Julia Ellsworth, 1859-1950. (["Box 1, folder 12"])(1916 January 8)[Carman, Bliss]. https://collections.library.yale.edu/catalog/17167809.