MLA

Dreier, Katherine S. (Katherine Sophie), 1877-1952. Art Institute of Chicago. Box 3, folder 67-68. 1921-49. https://collections.library.yale.edu/catalog/16694404.

APA, 6th edition

Dreier, Katherine S. (Katherine Sophie), 1877-1952. (["Box 3, folder 67-68"])(1921-49)[Art Institute of Chicago]. https://collections.library.yale.edu/catalog/16694404.