MLA

Kissinger, Henry, 1923-2023. He. Box 26, folder 2. 2005. https://collections.library.yale.edu/catalog/12481353.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 26, folder 2"])(2005)[He]. https://collections.library.yale.edu/catalog/12481353.