Columbia subject headings:
Harvard subject headings:
China--History--220-589.
China--Social conditions--221 B.C.-960 A.D.
Clans--China
Nobility--China.
Princeton subject headings:
China--Intellectual life--221 B.C.-960 A.D.
Learning and scholarship--China--History.
Philosophy, Chinese--221 B.C.-960 A.D.