MLA

Erdoes, Richard, 1912-2008. "Fiesta". Box 49. 1975-1985, undated. https://collections.library.yale.edu/catalog/2079901.

APA, 6th edition

Erdoes, Richard, 1912-2008. (["Box 49"])(1975-1985, undated)["Fiesta"]. https://collections.library.yale.edu/catalog/2079901.