MLA

Lewis Theobald [Graphic]. Pubd. Jany. 20th 1794 by Wm. Richardson, Castle St., Leicester Fields, 0AD. https://collections.library.yale.edu/catalog/16193946.

APA, 6th edition

Lewis Theobald [graphic]. (0 C.E.). [Portraits, Portrait prints, Engravings England London 1794]. Pubd. Jany. 20th 1794 by Wm. Richardson, Castle St., Leicester Fields. https://collections.library.yale.edu/catalog/16193946.