MLA

McBride, Henry, 1867-1962. Duchamp, Marcel. Box 30 (Oversize), folder 733. n.d.. https://collections.library.yale.edu/catalog/2003783.

APA, 6th edition

McBride, Henry, 1867-1962. (["Box 30 (Oversize), folder 733"])(n.d.)[Duchamp, Marcel]. https://collections.library.yale.edu/catalog/2003783.