MLA

Dreier, Katherine S. (Katherine Sophie), 1877-1952. [Woman wearing hat]. Box 72, folder 1863. n.d.. https://collections.library.yale.edu/catalog/17047970.

APA, 6th edition

Dreier, Katherine S. (Katherine Sophie), 1877-1952. (["Box 72, folder 1863"])(n.d.)[[Woman wearing hat]]. https://collections.library.yale.edu/catalog/17047970.