MLA

Erdoes, Richard, 1912-2008. "Chama River Erosions". Box 79. 1975-1981, undated. https://collections.library.yale.edu/catalog/2101209.

APA, 6th edition

Erdoes, Richard, 1912-2008. (["Box 79"])(1975-1981, undated)["Chama River Erosions"]. https://collections.library.yale.edu/catalog/2101209.