MLA

Kissinger, Henry, 1923-2023. Frei-Freu. Box 310, folder 10. 1959. https://collections.library.yale.edu/catalog/11774640.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 310, folder 10"])(1959)[Frei-Freu]. https://collections.library.yale.edu/catalog/11774640.