MLA

Saarinen, Eero, 1910-1961. Tomar. Box 12, folder 188. undated. https://collections.library.yale.edu/catalog/10020348.

APA, 6th edition

Saarinen, Eero, 1910-1961. (["Box 12, folder 188"])(undated)[Tomar]. https://collections.library.yale.edu/catalog/10020348.