Music/Unidentified/Piano music in two movements, with sketches
MLA
Koch, Frederick R. (Frederick Robinson). Music/Unidentified/Piano music in two movements, with sketches. Box 346, folder 2055. n.d.. https://collections.library.yale.edu/catalog/2043683.
APA, 6th edition
Koch, Frederick R. (Frederick Robinson). (["Box 346, folder 2055"])(n.d.)[Music/Unidentified/Piano music in two movements, with sketches]. https://collections.library.yale.edu/catalog/2043683.