MLA

Clark, Warren Vester, 1821-1898. Warren Vester Clark, Rail Road Flat, California, to Wilson Hart Clark, New Haven, Connecticut. Box 1 | Folder 19. 1859 June 1. https://collections.library.yale.edu/catalog/17356876.

APA, 6th edition

Clark, Warren Vester, 1821-1898. (["Box 1 | Folder 19"])(1859 June 1)[Warren Vester Clark, Rail Road Flat, California, to Wilson Hart Clark, New Haven, Connecticut]. https://collections.library.yale.edu/catalog/17356876.