Columbia subject headings:
Iron implements--Korea--History--To 935.
Korea--Antiquities.
Korea--Civilization--To 935.
Harvard subject headings:
Iron implements--Korea--History--To 935.
Korea--Antiquities.
Korea--Civilization--To 935.
Princeton subject headings:
Iron implements--Korea--History.
Japan--Civilization--Korean influences.
Korea--Antiquities.
Korea--Civilization--To 935.