MLA

Kissinger, Henry, 1923-2023. Correspondence. Box 261, folder 6. 1957 October-December. https://collections.library.yale.edu/catalog/11786744.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 261, folder 6"])(1957 October-December)[Correspondence]. https://collections.library.yale.edu/catalog/11786744.