MLA

Du Bois, W. E. B. (William Edward Burghardt), 1868-1963. Partington, Paul. Box 1, folder 12-13. 1961-70. https://collections.library.yale.edu/catalog/2040336.

APA, 6th edition

Du Bois, W. E. B. (William Edward Burghardt), 1868-1963. (["Box 1, folder 12-13"])(1961-70)[Partington, Paul]. https://collections.library.yale.edu/catalog/2040336.