MLA

Kilpatrick, Jack Frederick (1915-1967). Hymn book. Box 13, folder 1110. undated. https://collections.library.yale.edu/catalog/15504933.

APA, 6th edition

Kilpatrick, Jack Frederick (1915-1967). (["Box 13, folder 1110"])(undated)[Hymn book]. https://collections.library.yale.edu/catalog/15504933.