MLA

Mason, John T., b. 1822. Ambrotype of an unidentified woman. Box 2 | Folder 14. n.d.. https://collections.library.yale.edu/catalog/16597820.

APA, 6th edition

Mason, John T., b. 1822. (["Box 2 | Folder 14"])(n.d.)[Ambrotype of an unidentified woman]. https://collections.library.yale.edu/catalog/16597820.