MLA

Eliot, George, 1819-1880. Letter. Box 11. 1944 Jan 18. https://collections.library.yale.edu/catalog/32365700.

APA, 6th edition

Eliot, George, 1819-1880. (["Box 11"])(1944 Jan 18)[Letter]. https://collections.library.yale.edu/catalog/32365700.