MLA

Horstmann, Dorothy M. (Dorothy Millicent), 1911-. General. Box 43, folder 16. 1959. https://collections.library.yale.edu/catalog/10015653.

APA, 6th edition

Horstmann, Dorothy M. (Dorothy Millicent), 1911-. (["Box 43, folder 16"])(1959)[General]. https://collections.library.yale.edu/catalog/10015653.