MLA

Kissinger, Henry, 1923-2023. Libich, Suzana. Box 301, folder 10. 1968-1969, undated. https://collections.library.yale.edu/catalog/11774516.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 301, folder 10"])(1968-1969, undated)[Libich, Suzana]. https://collections.library.yale.edu/catalog/11774516.