MLA

Van Vechten, Carl, 1880-1964. Dolin, Anton, in The Nutcracker, choreographed by Marius Petipa and Lev Ivanov. Box 344, folder 4489. 1944 May 18. https://collections.library.yale.edu/catalog/2033114.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 344, folder 4489"])(1944 May 18)[Dolin, Anton, in The Nutcracker, choreographed by Marius Petipa and Lev Ivanov]. https://collections.library.yale.edu/catalog/2033114.