MLA

Marinetti, F. T., 1876-1944. Futurisme: Adhésions et objections... " Poesia. With letters to Marinetti from Paul Adam and Robert de Montesquiou. [363-1]. box 5, slide 43. no date. https://collections.library.yale.edu/catalog/10648834.

APA, 6th edition

Marinetti, F. T., 1876-1944. (["box 5, slide 43"])(no date)[Futurisme: Adhésions et objections... " Poesia. With letters to Marinetti from Paul Adam and Robert de Montesquiou. [363-1]]. https://collections.library.yale.edu/catalog/10648834.