MLA

Harding, G. P. (George Perfect), 1780-1853, artist. La Comtesse de Koningsmark; Diana Saxonica [art original]. 1805.. https://collections.library.yale.edu/catalog/16704409.

APA, 6th edition

Harding, G. P. (George Perfect), 1780-1853, artist. (1805.)[La Comtesse de Koningsmark; Diana Saxonica [art original]]. https://collections.library.yale.edu/catalog/16704409.