MLA

Steinberg, Saul, 1914-1999. Untitled [Passport document]. Box 78, folder 1534. undated. https://collections.library.yale.edu/catalog/32457106.

APA, 6th edition

Steinberg, Saul, 1914-1999. (["Box 78, folder 1534"])(undated)[Untitled [Passport document]]. https://collections.library.yale.edu/catalog/32457106.