Columbia subject headings:
China--Boundaries.
China--History--Errors, inventions, etc.
China--History--Song dynasty, 960-1279.
China--History--Tang dynasty, 618-907.
Harvard subject headings:
China--History--Song dynasty, 960-1279.
China--History--Tang dynasty, 618-907.
Minorities--China--History
Princeton subject headings:
China--History--Song dynasty, 960-1279.
China--History--Tang dynasty, 618-907.
Minorities--China--History.