 A famous triad from the Gansong Art Museum nearly identical to the North Korean triad is usually attributed to the Goguryeo Kingdom and is typically dated to 563, showing that styles from 539 were still popular more than two decades later.Finally, some scholars suggest that a mandorla excavated in North Chungcheong Province should be dated to 536.The single-mandorla triad was a very popular type of image in the 6th century, with several whole triads surviving as well as figures surviving without mandorla and mandorla surviving without figures.