MLA

Kissinger, Henry, 1923-2023. O. Box 612, folder 7. 1997-1998. https://collections.library.yale.edu/catalog/11780236.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 612, folder 7"])(1997-1998)[O]. https://collections.library.yale.edu/catalog/11780236.