1. Lawson, T. (1997), Economics and Reality, London: Routledge
2. Ross, D. (1991), The Origins of American Social Science, Cambridge: Cambridge University Press
3. James, W. (1893), The Principles of Psychology, 2nd edn. New York: Holt
4. Freeman, C. (ed.) (1990), The Economics of Innovation, Aldershot: Edward Elgar
5. The Concept of Habit in Economic Analysis