MLA

Albers, Josef, 1888-1976. Black Mountain College. Box 3, folder 34-37. 1935-1948, undated. https://collections.library.yale.edu/catalog/10015083.

APA, 6th edition

Albers, Josef, 1888-1976. (["Box 3, folder 34-37"])(1935-1948, undated)[Black Mountain College]. https://collections.library.yale.edu/catalog/10015083.