Aristotle. “Aristotle’s Politics.” Google Books, March 29, 2013. https://books.google.com/books?id=DJP44GomyNoC&dq=Aristotle%27s%2B%22Politics%22&lr=&source=gbs_navlinks_s.
Hornblower, Simon. “Herodotus: Histories, Book 6.” Google Books, December 21, 2017. https://books.google.com/books?id=SgVADwAAQBAJ&dq=Herodotus%27%2B%22Histories%22&lr=&source=gbs_navlinks_s.
Plato, and Henry Desmond Pritchard Lee. “The Republic.” Google Books, March 1974. https://books.google.com/books/about/The_Republic.html?id=v_BpLwLKFPsC
Sophocles. “Sophocles: Antigone.” Google Books, September 9, 1999. https://books.google.com/books?id=WrEJrSGG018C&dq=Sophocles%27%2B%22Antigone%22&lr=&source=gbs_navlinks_s.
Thucydides. “Thucydides: History of the Peloponnesian War Books I and II.” Google Books, 1919. https://books.google.com/books?id=qxaPjfUMTNAC&dq=Thucydides%27%2B%22History%2Bof%2Bthe%2BPeloponnesian%2BWar%22&lr=&source=gbs_navlinks_s.