MLA

Kissinger, Henry, 1923-2023. A. Box 296, folder 1. 1969-1977. https://collections.library.yale.edu/catalog/11774417.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 296, folder 1"])(1969-1977)[A]. https://collections.library.yale.edu/catalog/11774417.