MLA

Robertson, Archibald, 1765-1835. Archd. Robertson, print-seller and drawing-master, in Savill Row Passage, adjoining Squib's auction room sells great variety of Italian, French and Dutch prints and drawings; best Swiss-crayons, variety of drawing paper, port crayons, all sorts of Italian and French chalks ... [graphic]. [approximately 1777]. https://collections.library.yale.edu/catalog/33117820.

APA, 6th edition

Robertson, Archibald, 1765-1835. ([approximately 1777])[Archd. Robertson, print-seller and drawing-master, in Savill Row Passage, adjoining Squib's auction room sells great variety of Italian, French and Dutch prints and drawings; best Swiss-crayons, variety of drawing paper, port crayons, all sorts of Italian and French chalks ... [graphic]]. https://collections.library.yale.edu/catalog/33117820.