MLA

Kissinger, Henry, 1923-2023. Dillon, Douglas. Box 300, folder 8. 1968. https://collections.library.yale.edu/catalog/11774497.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 300, folder 8"])(1968)[Dillon, Douglas]. https://collections.library.yale.edu/catalog/11774497.