Columbia subject headings:
Japan--History--645-794--Sources.
Japan--History--Heian period, 794-1185--Sources.
Harvard subject headings:
Japan--History--645-794--Sources.
Japan--History--Heian period, 794-1185--Sources.
Princeton subject headings:
Japan--History--645-794--Sources.
Japan--History--Heian period, 794-1185--Sources.