1. Evolution: why the whole is greater than the sum of its parts;Allen,1988
2. Why the future is not what it was;Allen;Futures,1990
3. Allen, P.M., Evolution: persistent ignorance from continual learning. In: Nonlinear Dynamics and Evolutionary Economics. Oxford: Oxford University Press, 1993, 101-112.
4. Evolving complexity in social science;Allen,1998
5. Knowledge, ignorance and the evolution of complex systems;Allen,2001