MLA

Broch, Hermann, 1886-1951. Script, "Das unbekannte X: Der Film einer physikalischen Theorie," bound, typescript, carbon, corrected. Box 42, folder 956. n.d.. https://collections.library.yale.edu/catalog/17268017.

APA, 6th edition

Broch, Hermann, 1886-1951. (["Box 42, folder 956"])(n.d.)[Script, "Das unbekannte X: Der Film einer physikalischen Theorie," bound, typescript, carbon, corrected]. https://collections.library.yale.edu/catalog/17268017.