MLA

Van Vechten, Carl, 1880-1964. Strayhorn, Billy. Box 105 | Folder 1914. 1958 August 19. https://collections.library.yale.edu/catalog/2028065.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 105 | Folder 1914"])(1958 August 19)[Strayhorn, Billy]. https://collections.library.yale.edu/catalog/2028065.