MLA

Tunnard, Christopher, 1910-1979. Clippings. Box 15, folder 237. 1956-1969, undated. https://collections.library.yale.edu/catalog/10014266.

APA, 6th edition

Tunnard, Christopher, 1910-1979. (["Box 15, folder 237"])(1956-1969, undated)[Clippings]. https://collections.library.yale.edu/catalog/10014266.