MLA

Kilpatrick, Jack Frederick (1915-1967). Hymn. Box 13, folder 1151. undated. https://collections.library.yale.edu/catalog/15530514.

APA, 6th edition

Kilpatrick, Jack Frederick (1915-1967). (["Box 13, folder 1151"])(undated)[Hymn]. https://collections.library.yale.edu/catalog/15530514.