MLA

Kissinger, Henry, 1923-2023. Richardson, John. Box 51, folder 5. 1960-1968. https://collections.library.yale.edu/catalog/11783344.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 51, folder 5"])(1960-1968)[Richardson, John]. https://collections.library.yale.edu/catalog/11783344.