MLA

Marinetti, F. T., 1876-1944. Eight clippings related to “Le Onoranzi nazionali Umberto Boccioni.” [6773-1]. box 85, slide 73. no date. https://collections.library.yale.edu/catalog/10659390.

APA, 6th edition

Marinetti, F. T., 1876-1944. (["box 85, slide 73"])(no date)[Eight clippings related to “Le Onoranzi nazionali Umberto Boccioni.” [6773-1]]. https://collections.library.yale.edu/catalog/10659390.