MLA

Kissinger, Henry, 1923-2023. John F. Kennedy Europe trip. Box 176, folder 2. 1963 June. https://collections.library.yale.edu/catalog/11785371.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 176, folder 2"])(1963 June)[John F. Kennedy Europe trip]. https://collections.library.yale.edu/catalog/11785371.