MLA

Marinetti, F. T., 1876-1944. Anonymous. “Per Antonio Sant'Elia.” No source, [Il Broletto?], [1930]. With a caricature of Sant'Elia. [6955-1]. box 88, slide 15. 1930. https://collections.library.yale.edu/catalog/10659666.

APA, 6th edition

Marinetti, F. T., 1876-1944. (["box 88, slide 15"])(1930)[Anonymous. “Per Antonio Sant'Elia.” No source, [Il Broletto?], [1930]. With a caricature of Sant'Elia. [6955-1]]. https://collections.library.yale.edu/catalog/10659666.