MLA

Backus, Isaac, 1724-1806. Collected papers. box 8, folder 30. 1768 September 2–1768 September 12. https://collections.library.yale.edu/catalog/33555870.

APA, 6th edition

Backus, Isaac, 1724-1806. (["box 8, folder 30"])(1768 September 2–1768 September 12)[Collected papers]. https://collections.library.yale.edu/catalog/33555870.