MLA

Carter, John, 1748-1817, artist. Front, back and side of the model of the tomb of Sr. Thomas Becket in enamel, size of the original. [art original]. [approximately 1790]. https://collections.library.yale.edu/catalog/16729765.

APA, 6th edition

Carter, John, 1748-1817, artist. ([approximately 1790])[Front, back and side of the model of the tomb of Sr. Thomas Becket in enamel, size of the original. [art original]]. https://collections.library.yale.edu/catalog/16729765.