1850
MLA
Cooper, James Fenimore, 1789-1851. 1850. Box 29, folder 559. undated. https://collections.library.yale.edu/catalog/12336210.
APA, 6th edition
Cooper, James Fenimore, 1789-1851. (["Box 29, folder 559"])(undated)[1850]. https://collections.library.yale.edu/catalog/12336210.