MLA

Kissinger, Henry, 1923-2023. Young, Elizabeth and Wayland. Box 64, folder 21. 1964-1965. https://collections.library.yale.edu/catalog/11783659.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 64, folder 21"])(1964-1965)[Young, Elizabeth and Wayland]. https://collections.library.yale.edu/catalog/11783659.