MLA

Lewis, Sinclair, 1885-1951. Drafts. Box 7, folder 46-51. undated. https://collections.library.yale.edu/catalog/32257998.

APA, 6th edition

Lewis, Sinclair, 1885-1951. (["Box 7, folder 46-51"])(undated)[Drafts]. https://collections.library.yale.edu/catalog/32257998.