Barker, E. S. (1960). Greek political theory: Plato and his predecessors. Methuen.
Chicago-viite (17. p.)Barker, Ernest Sir. Greek Political Theory: Plato and His Predecessors. London: Methuen, 1960.
MLA-viite (9. p.)Barker, Ernest Sir. Greek Political Theory: Plato and His Predecessors. Methuen, 1960.
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