MLA

Boswell, James, 1740-1795. "A Letter from James Boswell, An Account of the Armed Corsican Chief" London Magazine. Box 64, folder 1322. 1769. https://collections.library.yale.edu/catalog/32584707.

APA, 6th edition

Boswell, James, 1740-1795. (["Box 64, folder 1322"])(1769)["A Letter from James Boswell, An Account of the Armed Corsican Chief" London Magazine]. https://collections.library.yale.edu/catalog/32584707.