MLA

Van Vechten, Carl, 1880-1964. Peterson, Dorothy Randolph. Box 101 | Folder 1810. 1937 July 11. https://collections.library.yale.edu/catalog/2027163.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 101 | Folder 1810"])(1937 July 11)[Peterson, Dorothy Randolph]. https://collections.library.yale.edu/catalog/2027163.