APA
Barker S. E., . (1960). Greek political theory. London: Barnes & Noble.
Chicago
Barker Sir Ernest, . 1960. Greek political theory. London: Barnes & Noble.
Harvard
Barker S. E., . (1960). Greek political theory. London: Barnes & Noble.
MLA
Barker Sir Ernest, . Greek political theory. London: Barnes & Noble. 1960.