MLA

Collings, Samuel, and printmaker. Doctor Phlogiston, the Priestley Politician or the Political Priest! [Graphic]. Published as the act directs by W. Locke, 0AD. https://collections.library.yale.edu/catalog/17338409.

APA, 6th edition

Collings, S., & printmaker. (0 C.E.). Doctor Phlogiston, the priestley politician or the political priest! [graphic] [Caricatures and cartoons, Caricatures, Etchings, Satires (Visual works) England 1791, Etchings England London 1791]. Published as the act directs by W. Locke. https://collections.library.yale.edu/catalog/17338409.