Columbia subject headings:
China--History--Song dynasty, 960-1279.
China--History--Yuan dynasty, 1260-1368.
Harvard subject headings:
China--History--Song dynasty, 960-1279.
China--History--Yuan dynasty, 1260-1368.
Princeton subject headings:
China--History--Song dynasty, 960-1279.
China--History--Yuan dynasty, 1260-1368.