MLA

Geldzahler, Henry, 1935-1994. Essay on Albert Pinkham Ryder: an important area of study for Geldzahler in the 1960s. Box 5, folder 189. circa 1945-1996. https://collections.library.yale.edu/catalog/17185207.

APA, 6th edition

Geldzahler, Henry, 1935-1994. (["Box 5, folder 189"])(circa 1945-1996)[Essay on Albert Pinkham Ryder: an important area of study for Geldzahler in the 1960s]. https://collections.library.yale.edu/catalog/17185207.