MLA

Steinberg, Saul, 1914-1999. Untitled [Man carrying basket and staff in abstract landscape; Study of abstract clouds]. Box 75, folder 1364. undated. https://collections.library.yale.edu/catalog/16855645.

APA, 6th edition

Steinberg, Saul, 1914-1999. (["Box 75, folder 1364"])(undated)[Untitled [Man carrying basket and staff in abstract landscape; Study of abstract clouds]]. https://collections.library.yale.edu/catalog/16855645.