MLA

Diana in the Carlo Maratt Room at Houghton / [Graphic]. Publish'd Sept. 1st, 1785, by John Boydell, engraver, in Cheapside, 0AD. https://collections.library.yale.edu/catalog/15808917.

APA, 6th edition

Diana in the Carlo Maratt room at Houghton / [graphic]. (0 C.E.). [Reproductions, Stipple engravings England London 1785]. Publish'd Sept. 1st, 1785, by John Boydell, engraver, in Cheapside. https://collections.library.yale.edu/catalog/15808917.