MLA

Clark, Warren Vester, 1821-1898. Warren Vester Clark, Rail Road Flat, California, to Wilson Hart Clark, New Haven, Connecticut. Box 1 | Folder 36. 1868 September 22. https://collections.library.yale.edu/catalog/17356885.

APA, 6th edition

Clark, Warren Vester, 1821-1898. (["Box 1 | Folder 36"])(1868 September 22)[Warren Vester Clark, Rail Road Flat, California, to Wilson Hart Clark, New Haven, Connecticut]. https://collections.library.yale.edu/catalog/17356885.