MLA

Purdy, James, 1914-2009. Desnos, Edmundo. Box 1, folder 22. 1958-65. https://collections.library.yale.edu/catalog/32210194.

APA, 6th edition

Purdy, James, 1914-2009. (["Box 1, folder 22"])(1958-65)[Desnos, Edmundo]. https://collections.library.yale.edu/catalog/32210194.