MLA

Scheuer, Steven H., 1926-2014. A Christmas Surprise Paul Crabtree. Box 365, folder 4. 1956 Dec 24. https://collections.library.yale.edu/catalog/17101448.

APA, 6th edition

Scheuer, Steven H., 1926-2014. (["Box 365, folder 4"])(1956 Dec 24)[A Christmas Surprise Paul Crabtree]. https://collections.library.yale.edu/catalog/17101448.