Cite

Music/Symphony, no. 2: first movement

MLA

Koch, Frederick R. (Frederick Robinson). Music/Symphony, no. 2: first movement. Box 340, folder 1989. n.d.. https://collections.library.yale.edu/catalog/2067774.

APA, 6th edition

Koch, Frederick R. (Frederick Robinson). (["Box 340, folder 1989"])(n.d.)[Music/Symphony, no. 2: first movement]. https://collections.library.yale.edu/catalog/2067774.