1. Aristotle. 1988. The Politics (Edited by Stephen Everson). Cambridge, MA, Cambridge University Press.
2. Constant, B. 1970. Principles of Politics Applicable to All Governments. Indianapolis, IN, Liberty Fund.
3. Constant, B. 1988. The liberty of ancients compared with that of modern. In B. Constant (Ed.), Political Writings. Cambridge, MA, Cambridge University Press.
4. Dahl, R. 1998. On Democracy. New Haven, CT, Yale University Press.
5. del Águila, R. 1998. Los precursores de la idea de democracia: la democracia ateniense. In R. del Águila, F. Vallespín et al. (Eds.), La democracia en sus textos. Madrid, Alianza Editorial.