MLA

Kissinger, Henry, 1923-2023. Z. Box 17, folder 7. 2003. https://collections.library.yale.edu/catalog/12481867.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 17, folder 7"])(2003)[Z]. https://collections.library.yale.edu/catalog/12481867.