MLA

Stein, Gertrude, 1874-1946. Manuscript notebooks. Box 72, folder 1318-1321. [1921]. https://collections.library.yale.edu/catalog/10596184.

APA, 6th edition

Stein, Gertrude, 1874-1946. (["Box 72, folder 1318-1321"])([1921])[Manuscript notebooks]. https://collections.library.yale.edu/catalog/10596184.