MLA

Van Thal, Herbert, 1904-1983. "R" general. Box 2, folder 102. 1941-70. https://collections.library.yale.edu/catalog/16546006.

APA, 6th edition

Van Thal, Herbert, 1904-1983. (["Box 2, folder 102"])(1941-70)["R" general]. https://collections.library.yale.edu/catalog/16546006.