MLA

Koch, Frederick R. (Frederick Robinson). Music/Canzone popolare. Box 326, folder 1792. 1882 Jun 1. https://collections.library.yale.edu/catalog/2043986.

APA, 6th edition

Koch, Frederick R. (Frederick Robinson). (["Box 326, folder 1792"])(1882 Jun 1)[Music/Canzone popolare]. https://collections.library.yale.edu/catalog/2043986.