MLA

The Quintessence of Quackism ... [Graphic]. Publish'd as the Act directs. Oct 30th. 1780. P. Mitchel North Audley St. Grosvenor Sq., 0AD. https://collections.library.yale.edu/catalog/17338578.

APA, 6th edition

The quintessence of quackism ... [graphic]. (0 C.E.). [Songs 1798, Satires (Visual works), Etchings]. Publish'd as the Act directs. Oct 30th. 1780. P. Mitchel North Audley St. Grosvenor Sq. https://collections.library.yale.edu/catalog/17338578.