MLA

Kissinger, Henry, 1923-2023. Blair, Tony. Box 631, folder 4. 2000. https://collections.library.yale.edu/catalog/11780472.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 631, folder 4"])(2000)[Blair, Tony]. https://collections.library.yale.edu/catalog/11780472.