MLA

Keller, Deane, 1901-1992. Biographical. Box 1, folder 2. 1925, 1942, 1980, undated. https://collections.library.yale.edu/catalog/10015661.

APA, 6th edition

Keller, Deane, 1901-1992. (["Box 1, folder 2"])(1925, 1942, 1980, undated)[Biographical]. https://collections.library.yale.edu/catalog/10015661.