MLA

Schaefer, F. L. Interstitial Pulmonary Emphysema. 1919. https://collections.library.yale.edu/catalog/15947985.

APA, 6th edition

Schaefer, F. L. (1919). Interstitial Pulmonary Emphysema [Drawings (AAT)]. https://collections.library.yale.edu/catalog/15947985.