MLA

Jeleński, Konstanty A. (Konstanty Aleksander), 1922-1987. "The seminar program of the Congress," typescript (copy) with notes by Jeleński. Box 13, folder 337. undated. https://collections.library.yale.edu/catalog/16612903.

APA, 6th edition

Jeleński, Konstanty A. (Konstanty Aleksander), 1922-1987. (["Box 13, folder 337"])(undated)["The seminar program of the Congress," typescript (copy) with notes by Jeleński]. https://collections.library.yale.edu/catalog/16612903.