MLA

Steinberg, Saul, 1914-1999. Untitled [Heraldic subject]. Box 79, folder 1658. undated. https://collections.library.yale.edu/catalog/32479119.

APA, 6th edition

Steinberg, Saul, 1914-1999. (["Box 79, folder 1658"])(undated)[Untitled [Heraldic subject]]. https://collections.library.yale.edu/catalog/32479119.