MLA

Zilboorg, Gregory, 1890-1959. Research notes, holograph. Box 3, folder 28-31. 1910s-1925. https://collections.library.yale.edu/catalog/17085337.

APA, 6th edition

Zilboorg, Gregory, 1890-1959. (["Box 3, folder 28-31"])(1910s-1925)[Research notes, holograph]. https://collections.library.yale.edu/catalog/17085337.