MLA

Kilpatrick, Jack Frederick (1915-1967). Sunday School notes. Box 1, folder 62. 1935 September 9. https://collections.library.yale.edu/catalog/15492063.

APA, 6th edition

Kilpatrick, Jack Frederick (1915-1967). (["Box 1, folder 62"])(1935 September 9)[Sunday School notes]. https://collections.library.yale.edu/catalog/15492063.