MLA

Smith, John Raphael, 1752-1812, printmaker. Schoolboys [graphic]. [ca. August 1778?]. https://collections.library.yale.edu/catalog/11134629.

APA, 6th edition

Smith, John Raphael, 1752-1812, printmaker. ([ca. August 1778?])[Schoolboys [graphic]]. https://collections.library.yale.edu/catalog/11134629.