MLA

Van Vechten, Carl, 1880-1964. Douglas, Norman, and Carl Van Vechten at Parco delle Cascine, Florence, Italy. Box 473, folder 8039. 1935 June 23. https://collections.library.yale.edu/catalog/2033414.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 473, folder 8039"])(1935 June 23)[Douglas, Norman, and Carl Van Vechten at Parco delle Cascine, Florence, Italy]. https://collections.library.yale.edu/catalog/2033414.