MLA

Steinberg, Saul, 1914-1999. Untitled [Two women]. Box 78, folder 1583. undated. https://collections.library.yale.edu/catalog/32457454.

APA, 6th edition

Steinberg, Saul, 1914-1999. (["Box 78, folder 1583"])(undated)[Untitled [Two women]]. https://collections.library.yale.edu/catalog/32457454.