MLA

Kissinger, Henry, 1923-2023. Zinberg, Dorothy. Box 202, folder 18. 1968 March. https://collections.library.yale.edu/catalog/11785901.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 202, folder 18"])(1968 March)[Zinberg, Dorothy]. https://collections.library.yale.edu/catalog/11785901.