1. P. J. Flory, Principles of Polymer Chemistry, Cornell University Press, Ithaca, NY, 1953.
2. J.M.G. Cowie, Polymers: Chemistry and Physics of Modern Materials, Blackie, Chapman and Hall, London, 1973 and 1991.
3. J.A. Semlyen (ed.), Cyclic Polymers, Elsevier Applied Science, London, 1986.
4. F. Jacob and E.L. Wollman, Symp. Soc. Exp. Biol., 12, 75 (1958).
5. W. Fiers and R.L. Sinsheimer, J. Mol. Biol., 5, 408 (1962).