MLA

Beinecke, Edwin J. (Edwin John), 1886-1970. Simoneau, Jules. Box 64, folder 1483. undated. https://collections.library.yale.edu/catalog/16609943.

APA, 6th edition

Beinecke, Edwin J. (Edwin John), 1886-1970. (["Box 64, folder 1483"])(undated)[Simoneau, Jules]. https://collections.library.yale.edu/catalog/16609943.