MLA

Backus, Isaac, 1724-1806. Collected papers. box 9, folder 41. 1773 October 16–1773 November 5. https://collections.library.yale.edu/catalog/33579986.

APA, 6th edition

Backus, Isaac, 1724-1806. (["box 9, folder 41"])(1773 October 16–1773 November 5)[Collected papers]. https://collections.library.yale.edu/catalog/33579986.