MLA

Kissinger, Henry, 1923-2023. Correspondence. Box 261, folder 2. 1956 May-1957 June. https://collections.library.yale.edu/catalog/11786740.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 261, folder 2"])(1956 May-1957 June)[Correspondence]. https://collections.library.yale.edu/catalog/11786740.