MLA

Bergery, Bettina, 1902-1993. Bergery, Bettina and others in French Equatorial Africa. Box 46. circa 1900-circa 1990. https://collections.library.yale.edu/catalog/2020407.

APA, 6th edition

Bergery, Bettina, 1902-1993. (["Box 46"])(circa 1900-circa 1990)[Bergery, Bettina and others in French Equatorial Africa]. https://collections.library.yale.edu/catalog/2020407.