[Symphony, no. 1, op. 21, C major]
MLA
Beethoven, Ludwig van, 1770-1827. [Symphony, no. 1, op. 21, C major]. Box 187 | Folder 963 : Original folder. [1807?]. https://collections.library.yale.edu/catalog/15491314.
APA, 6th edition
Beethoven, Ludwig van, 1770-1827. (["Box 187 | Folder 963 : Original folder"])([1807?])[[Symphony, no. 1, op. 21, C major]]. https://collections.library.yale.edu/catalog/15491314.