MLA

Van Vechten, Carl, 1880-1964. Karnakoski, Kari, as the Prince in Sebastian, ballet choreographed by Edward Caton. Box 355, folder 4817. 1944 November 20. https://collections.library.yale.edu/catalog/2054495.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 355, folder 4817"])(1944 November 20)[Karnakoski, Kari, as the Prince in Sebastian, ballet choreographed by Edward Caton]. https://collections.library.yale.edu/catalog/2054495.