MLA

Ulmann, Doris, d. 1934. Harvey Cushing by Doris Ulmann. 1920s. https://collections.library.yale.edu/catalog/15951362.

APA, 6th edition

Ulmann, Doris, d. 1934. (1920s)[Harvey Cushing by Doris Ulmann]. https://collections.library.yale.edu/catalog/15951362.