1. J. Rosen,A Symmetry Primer for Scientists (Wiley, New York, 1983).
2. J. Rosen,Symmetry Discovered: Concepts and Applications in Nature and Science (Cambridge University Press, Cambridge, 1975), Chap. 4.
3. W. B. Jensen, ?Classification, symmetry and the periodic table,? Comput. Math. Appl.128, 487?510 (1986), reprinted inSymmetry, Unifying Human Understanding, I. Hargittai, ed. (Pergamon, New York, 1986), pp. 487?510.
4. J. N. Shive and R. L. Weber,Similarities in Physics (Wiley, New York, 1982).
5. J. Rosen, ?The anthropic principle,?Am. J. Phys. 53, 335?339 (1985).