MLA

Wilfred, Thomas, 1889-1968. Odd instruments. Box 15, folder 212. Undated. https://collections.library.yale.edu/catalog/10015540.

APA, 6th edition

Wilfred, Thomas, 1889-1968. (["Box 15, folder 212"])(Undated)[Odd instruments]. https://collections.library.yale.edu/catalog/10015540.