MLA

Kissinger, Henry, 1923-2023. L. Box 556, folder 7. 1986. https://collections.library.yale.edu/catalog/11779504.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 556, folder 7"])(1986)[L]. https://collections.library.yale.edu/catalog/11779504.