1. Ackrill, J. L. (1981). Aristotle the philosopher. Oxford: Oxford University Press.
2. Aristotle (1984a). Ethica Nicomachea. In Barnes J. (Ed.), The complete works of Aristotle. Princeton: Princeton university press.
3. Aristotle (1984b). Posterior analytics. In Barnes J. (Ed.), The complete works of Aristotle, Princeton: Princeton university press.
4. Ashby, W. R. (1958). An introduction to cybernetics. London: Chapman and Hall.
5. Beer, S. (1979). The heart of enterprise. New York: Wiley.