Music/Sonata, string orchestra, A minor
MLA
Koch, Frederick R. (Frederick Robinson). Music/Sonata, string orchestra, A minor. Box 219, folder 1561. n.d.. https://collections.library.yale.edu/catalog/2077424.
APA, 6th edition
Koch, Frederick R. (Frederick Robinson). (["Box 219, folder 1561"])(n.d.)[Music/Sonata, string orchestra, A minor]. https://collections.library.yale.edu/catalog/2077424.