MLA

Erdoes, Richard, 1912-2008. "Schweigman Eagle Feathers Wedding". Box 74. undated. https://collections.library.yale.edu/catalog/2097914.

APA, 6th edition

Erdoes, Richard, 1912-2008. (["Box 74"])(undated)["Schweigman Eagle Feathers Wedding"]. https://collections.library.yale.edu/catalog/2097914.