MLA

Kissinger, Henry, 1923-2023. Stoessinger, John. Box 202, folder 9. Circa 1968. https://collections.library.yale.edu/catalog/11785892.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 202, folder 9"])(Circa 1968)[Stoessinger, John]. https://collections.library.yale.edu/catalog/11785892.