MLA

Kissinger, Henry, 1923-2023. von Westphalen, Friedrich. Box 61, folder 22. 1968. https://collections.library.yale.edu/catalog/11783577.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 61, folder 22"])(1968)[von Westphalen, Friedrich]. https://collections.library.yale.edu/catalog/11783577.