MLA

Van Vechten, Carl, 1880-1964. [Christmas cards]. Box 249, folder 2802. 1925, undated. https://collections.library.yale.edu/catalog/10000263.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 249, folder 2802"])(1925, undated)[[Christmas cards]]. https://collections.library.yale.edu/catalog/10000263.