MLA

Kissinger, Henry, 1923-2023. Elliot, William Y.. Box 18, folder 14. 1959-1968. https://collections.library.yale.edu/catalog/11782633.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 18, folder 14"])(1959-1968)[Elliot, William Y.]. https://collections.library.yale.edu/catalog/11782633.