MLA

Kissinger, Henry, 1923-2023. E. Box 518, folder 14. 1993. https://collections.library.yale.edu/catalog/11778895.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 518, folder 14"])(1993)[E]. https://collections.library.yale.edu/catalog/11778895.