MLA

Koch, Frederick R. (Frederick Robinson). Music/Richard III. Box 214, folder 1556. 1955. https://collections.library.yale.edu/catalog/2035687.

APA, 6th edition

Koch, Frederick R. (Frederick Robinson). (["Box 214, folder 1556"])(1955)[Music/Richard III]. https://collections.library.yale.edu/catalog/2035687.