Columbia subject headings:
Harvard subject headings:
Byzantine Empire--History--1081-1453.
Byzantine Empire--History--527-1081.
Byzantine Empire--Relations--Holy Roman Empire.
City-states--Greece.
Greece--History--To 1500.
Greece--Politics and government--History.
Political science--Philosophy
Princeton subject headings:
Facsimiles.
Greece--Politics and government.
Political science.
Political sociology.