MLA

Bergery, Bettina, 1902-1993. Bergery, Bettina. Box 45. 1930s-50s. https://collections.library.yale.edu/catalog/16797067.

APA, 6th edition

Bergery, Bettina, 1902-1993. (["Box 45"])(1930s-50s)[Bergery, Bettina]. https://collections.library.yale.edu/catalog/16797067.