MLA

Kissinger, Henry, 1923-2023. Haskins, Caryl. Box 29, folder 3. 1964-1969, undated. https://collections.library.yale.edu/catalog/11782853.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 29, folder 3"])(1964-1969, undated)[Haskins, Caryl]. https://collections.library.yale.edu/catalog/11782853.