MLA

Van Vechten, Carl, 1880-1964. Golschmann, Vladimir. Box 350, folder 4673. 1937 June 29. https://collections.library.yale.edu/catalog/2035513.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 350, folder 4673"])(1937 June 29)[Golschmann, Vladimir]. https://collections.library.yale.edu/catalog/2035513.