MLA

Leoncavallo, Ruggiero, 1858-1919. Pirani. Box 10, folder 305. n.d.. https://collections.library.yale.edu/catalog/16666541.

APA, 6th edition

Leoncavallo, Ruggiero, 1858-1919. (["Box 10, folder 305"])(n.d.)[Pirani]. https://collections.library.yale.edu/catalog/16666541.