MLA

Kissinger, Henry, 1923-2023. Emmet, Christopher. Box 19, folder 1. 1962-1964 May. https://collections.library.yale.edu/catalog/11782639.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 19, folder 1"])(1962-1964 May)[Emmet, Christopher]. https://collections.library.yale.edu/catalog/11782639.