MLA

Chisholm, Hugh, 1913-1972. Chisholm, Hugh. Box 1 | Folder 8. undated. https://collections.library.yale.edu/catalog/17104135.

APA, 6th edition

Chisholm, Hugh, 1913-1972. (["Box 1 | Folder 8"])(undated)[Chisholm, Hugh]. https://collections.library.yale.edu/catalog/17104135.