MLA

Kissinger, Henry, 1923-2023. Havel, Václav with Kissinger. Box 227, folder 39. Undated, circa 1967-circa 2009. https://collections.library.yale.edu/catalog/12480462.

APA, 6th edition

Kissinger, Henry, 1923-2023. (["Box 227, folder 39"])(Undated, circa 1967-circa 2009)[Havel, Václav with Kissinger]. https://collections.library.yale.edu/catalog/12480462.