MLA

Clark, Rodney, 1824-1887. Rodney Clark and Martin Carrington, New Haven, Connecticut, to Wilson Hart Clark, New Haven, Connecticut. Box 1 | Folder 8. 1857 March 20. https://collections.library.yale.edu/catalog/17356867.

APA, 6th edition

Clark, Rodney, 1824-1887. (["Box 1 | Folder 8"])(1857 March 20)[Rodney Clark and Martin Carrington, New Haven, Connecticut, to Wilson Hart Clark, New Haven, Connecticut]. https://collections.library.yale.edu/catalog/17356867.