MLA

Zilboorg, Gregory, 1890-1959. Semelaigne, René. Box 2, folder 19. 1927-1930. https://collections.library.yale.edu/catalog/17085334.

APA, 6th edition

Zilboorg, Gregory, 1890-1959. (["Box 2, folder 19"])(1927-1930)[Semelaigne, René]. https://collections.library.yale.edu/catalog/17085334.