MLA

Ernest Augustus, King of Hanover, 1771-1851. [Symphony, no. 1, op. 21, C major]. Arranged by C. Kramer. Parts (3 fl, 5 cl, 2nd ob, 2 bn, spt, 1st hn, 2 tpt, 3 trbn, timp, unidentified). Manuscript. Box 187, folder 961-963. 1807?. https://collections.library.yale.edu/catalog/15491314.

APA, 6th edition

Ernest Augustus, King of Hanover, 1771-1851. (["Box 187, folder 961-963"])(1807?)[[Symphony, no. 1, op. 21, C major]. Arranged by C. Kramer. Parts (3 fl, 5 cl, 2nd ob, 2 bn, spt, 1st hn, 2 tpt, 3 trbn, timp, unidentified). Manuscript]. https://collections.library.yale.edu/catalog/15491314.