MLA

Dreier, Katherine S. (Katherine Sophie), 1877-1952. [Woman reflected in mirror]. Box 72, folder 1860. n.d.. https://collections.library.yale.edu/catalog/17047967.

APA, 6th edition

Dreier, Katherine S. (Katherine Sophie), 1877-1952. (["Box 72, folder 1860"])(n.d.)[[Woman reflected in mirror]]. https://collections.library.yale.edu/catalog/17047967.