1. Anderson, P.W.: More is different: broken symmetry and the nature of the hierarchical structure of science. Science 177, 393–396 (1972)
2. Atay, F., Jost, J.: On the emergence of complex systems on the basis of the coordination of complex behaviors of their elements. Complexity 10(1), 17–22 (2004)
3. Bar Yam, Y.: A mathematical theory of strong emergence using multiscale variety. Complexity 9(6), 15–24 (2004)
4. Bechtel, W., Richardson, R.: Emergent phenomena and complex systems. In: Beckermann, A., Flohr, H., Kim, J. (eds.) Emergence or Reduction? pp. 257–287. de Gruyter, Berlin (1992)
5. Bedau, M.: Weak emergence. In: Tomberlin, J. (ed.) Philosophical Perspectives: Mind, Causation, and World, vol. 11, pp. 375–399. Blackwell Publishers, Oxford (1997)