MLA

Nicholls, Norton, 1741?-1809. John Wheler to Norton Nicholls. London. Concerns Charles de Bonstetten; France. Box 1, folder 91. 1770 Mar 25. https://collections.library.yale.edu/catalog/17439888.

APA, 6th edition

Nicholls, Norton, 1741?-1809. (["Box 1, folder 91"])(1770 Mar 25)[John Wheler to Norton Nicholls. London. Concerns Charles de Bonstetten; France]. https://collections.library.yale.edu/catalog/17439888.