MLA

Marinetti, F. T., 1876-1944. Anonymous. “Il Teatro: Simultanina; la Voce Umana.” No source, [1931]. With 4 photos. [6715-1]. box 85, slide 15. 1931. https://collections.library.yale.edu/catalog/10659279.

APA, 6th edition

Marinetti, F. T., 1876-1944. (["box 85, slide 15"])(1931)[Anonymous. “Il Teatro: Simultanina; la Voce Umana.” No source, [1931]. With 4 photos. [6715-1]]. https://collections.library.yale.edu/catalog/10659279.