MLA

Erdoes, Richard, 1912-2008. Leonard Double Exposure. Box 75 | Sioux Ceremonies 2, Cheyennes. 1976, undated. https://collections.library.yale.edu/catalog/2098576.

APA, 6th edition

Erdoes, Richard, 1912-2008. (["Box 75 | Sioux Ceremonies 2, Cheyennes"])(1976, undated)[Leonard Double Exposure]. https://collections.library.yale.edu/catalog/2098576.