MLA

Berberova, N. (Nina), 1901-1993. Bunin, Ivan Alekseevich. Box 5, folder 99. 192?-46, n.d.. https://collections.library.yale.edu/catalog/16687989.

APA, 6th edition

Berberova, N. (Nina), 1901-1993. (["Box 5, folder 99"])(192?-46, n.d.)[Bunin, Ivan Alekseevich]. https://collections.library.yale.edu/catalog/16687989.