MLA

Saarinen, Eero, 1910-1961. Models. Box 64, folder 77. undated. https://collections.library.yale.edu/catalog/10016925.

APA, 6th edition

Saarinen, Eero, 1910-1961. (["Box 64, folder 77"])(undated)[Models]. https://collections.library.yale.edu/catalog/10016925.