MLA

Eliot, George, 1819-1880. Letter, Friday morning, to Mrs. Bray. Box 1. [1852 Jul 2]. https://collections.library.yale.edu/catalog/32366150.

APA, 6th edition

Eliot, George, 1819-1880. (["Box 1"])([1852 Jul 2])[Letter, Friday morning, to Mrs. Bray]. https://collections.library.yale.edu/catalog/32366150.