MLA

Lynes, George Platt, 1907-1955. Datebook. Box 2, folder 13. 1950. https://collections.library.yale.edu/catalog/17156219.

APA, 6th edition

Lynes, George Platt, 1907-1955. (["Box 2, folder 13"])(1950)[Datebook]. https://collections.library.yale.edu/catalog/17156219.