MLA

Williams, Charles, 1796-1866, printmaker. The hay-loft plot of Thistlewood and his 24 conspirators at 8 o'clock in Cato Street Edgeware Road London : to Massacre the Cabinet Ministers of King George the 4th at the Earl of Harrowby's Dinner Grosvenor Square 23d Feby 1820. [1820]. https://collections.library.yale.edu/catalog/33300081.

APA, 6th edition

Williams, Charles, 1796-1866, printmaker. ([1820])[The hay-loft plot of Thistlewood and his 24 conspirators at 8 o'clock in Cato Street Edgeware Road London : to Massacre the Cabinet Ministers of King George the 4th at the Earl of Harrowby's Dinner Grosvenor Square 23d Feby 1820]. https://collections.library.yale.edu/catalog/33300081.