MLA

Kissinger, Henry, 1923-2023. Schlesinger, Arthur, Jr.. Box 98, folder 18. 1961-1963. https://collections.library.yale.edu/catalog/11784090.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 98, folder 18"])(1961-1963)[Schlesinger, Arthur, Jr.]. https://collections.library.yale.edu/catalog/11784090.