MLA

A Horse with a Nose [Graphic]. Publish'd March 25th, 1791, by W. Dickinson, No. 25 Old Bond Street, 0AD. https://collections.library.yale.edu/catalog/17355589.

APA, 6th edition

A horse with a nose [graphic]. (0 C.E.). [Book illustrations, Satires (Visual works) England 1791, Etchings England London 1791, Stipple engravings England London 1791]. Publish'd March 25th, 1791, by W. Dickinson, No. 25 Old Bond Street. https://collections.library.yale.edu/catalog/17355589.