Cite

Music/Concerto, viola, orchestra: revised version

MLA

Koch, Frederick R. (Frederick Robinson). Music/Concerto, viola, orchestra: revised version. Box 201, folder 1543. [1961]. https://collections.library.yale.edu/catalog/2066504.

APA, 6th edition

Koch, Frederick R. (Frederick Robinson). (["Box 201, folder 1543"])([1961])[Music/Concerto, viola, orchestra: revised version]. https://collections.library.yale.edu/catalog/2066504.