MLA

Nicholls, Norton, 1741?-1809. Norton Nicholls to Jane Floyer Nicholls. Bologna. Concerns Norton Nicholls; mention of planned journals. Box 2, folder 175. 1772 Oct 17. https://collections.library.yale.edu/catalog/17439972.

APA, 6th edition

Nicholls, Norton, 1741?-1809. (["Box 2, folder 175"])(1772 Oct 17)[Norton Nicholls to Jane Floyer Nicholls. Bologna. Concerns Norton Nicholls; mention of planned journals]. https://collections.library.yale.edu/catalog/17439972.