MLA

Stein, Gertrude, 1874-1946. George Platt Lynes. Box 170, folder 4336. ca. 1927. https://collections.library.yale.edu/catalog/9998547.

APA, 6th edition

Stein, Gertrude, 1874-1946. (["Box 170, folder 4336"])(ca. 1927)[George Platt Lynes]. https://collections.library.yale.edu/catalog/9998547.