MLA

Bates, Ralph, 1899-2000. Oxford University Press. Box 1, folder 8. 1998 June 23. https://collections.library.yale.edu/catalog/2004446.

APA, 6th edition

Bates, Ralph, 1899-2000. (["Box 1, folder 8"])(1998 June 23)[Oxford University Press]. https://collections.library.yale.edu/catalog/2004446.