MLA

Schwartz, Delmore, 1913-1966. Reed, Lou. Box 1, folder 99. 1965. https://collections.library.yale.edu/catalog/10000119.

APA, 6th edition

Schwartz, Delmore, 1913-1966. (["Box 1, folder 99"])(1965)[Reed, Lou]. https://collections.library.yale.edu/catalog/10000119.