MLA

Stein, Gertrude, 1874-1946. About Gertrude Stein. Box 143, folder 3347-3350. 1930-32. https://collections.library.yale.edu/catalog/2065763.

APA, 6th edition

Stein, Gertrude, 1874-1946. (["Box 143, folder 3347-3350"])(1930-32)[About Gertrude Stein]. https://collections.library.yale.edu/catalog/2065763.