MLA

Kissinger, Henry, 1923-2023. Genscher, Hans Dietrich. Box 406, folder 9. 1977. https://collections.library.yale.edu/catalog/11777379.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 406, folder 9"])(1977)[Genscher, Hans Dietrich]. https://collections.library.yale.edu/catalog/11777379.