1. Aristotle. "Politics". In Everson, Stephen (ed.). The Politics and the Constitution of Athens. Cambridge, New York: Cambridge University Press. 1996
2. Habermas, Jürgen. The theory of communicative action. Boston: Beacon Press, 1984.
3. Koselleck, Reinhart e Richter, Michaela. "Crisis", Journal of the History of Ideas, v. 67, n. 2, p. 357-400, 2006.
4. Lovejoy, Arthur O. e Boas, George. Primitivism and related ideas in antiquity. Baltimore and London: John Hopkins University Press, 1935.
5. Machiavelli, Niccolò et al. Discourses on Livy. Chicago: University of Chicago Press, 1996.