MLA

Ernest Augustus, King of Hanover, 1771-1851. A New Series of Instructions Arranged Expressly for the Royal Portable Irish Harp.... Print (Dublin: for the author by John Egan). Box 454. 1822?. https://collections.library.yale.edu/catalog/10267808.

APA, 6th edition

Ernest Augustus, King of Hanover, 1771-1851. (["Box 454"])(1822?)[A New Series of Instructions Arranged Expressly for the Royal Portable Irish Harp.... Print (Dublin: for the author by John Egan)]. https://collections.library.yale.edu/catalog/10267808.