MLA

The Slough of Despond [Graphic]. publisher not identified, 0AD. https://collections.library.yale.edu/catalog/33121277.

APA, 6th edition

The slough of despond [graphic]. (0 C.E.). [Caricatures and cartoons, Satires (Visual works) England 1809, Etchings England London 1809]. publisher not identified. https://collections.library.yale.edu/catalog/33121277.