MLA

Erdoes, Richard, 1912-2008. "19th Century Paintings". Box 60. 1975-1986, undated. https://collections.library.yale.edu/catalog/2087406.

APA, 6th edition

Erdoes, Richard, 1912-2008. (["Box 60"])(1975-1986, undated)["19th Century Paintings"]. https://collections.library.yale.edu/catalog/2087406.