MLA

Marsh, Othniel Charles, 1831-1899. Ditte, Alfred. Box 9, folder 365A. 1899. https://collections.library.yale.edu/catalog/32556470.

APA, 6th edition

Marsh, Othniel Charles, 1831-1899. (["Box 9, folder 365A"])(1899)[Ditte, Alfred]. https://collections.library.yale.edu/catalog/32556470.