MLA

Boxers of Bangor, or, Messengers of Peace [Graphic]. Pubd. Augt. 6, 1796, by S.W. Fores, No. 50 Piccadilly, 0AD. https://collections.library.yale.edu/catalog/10952952.

APA, 6th edition

Boxers of Bangor, or, Messengers of peace [graphic]. (0 C.E.). [Caricatures and cartoons, Satires (Visual works) England 1796, Etchings England London 1796, Watermarks (Paper), Booksellers' stamps (Provenance) S. W. Fores]. Pubd. Augt. 6, 1796, by S.W. Fores, No. 50 Piccadilly. https://collections.library.yale.edu/catalog/10952952.