MLA

Reid, Whitelaw, 1837-1912. Whitman, Walt. Box 7. 1879 April 14. https://collections.library.yale.edu/catalog/10905235.

APA, 6th edition

Reid, Whitelaw, 1837-1912. (["Box 7"])(1879 April 14)[Whitman, Walt]. https://collections.library.yale.edu/catalog/10905235.