MLA

Kilpatrick, Jack Frederick (1915-1967). Sunday School texts. Box 1, folder 66. undated. https://collections.library.yale.edu/catalog/15492067.

APA, 6th edition

Kilpatrick, Jack Frederick (1915-1967). (["Box 1, folder 66"])(undated)[Sunday School texts]. https://collections.library.yale.edu/catalog/15492067.