1. 1) C. R. Robbins, “Chemical and Physical Behavior of Human Hair” 2nd edition, Springer-Verlag, New York, Berlin, Heidelberg (1988).
2. 2) H. Lindley, “Chemistry of Natural Protein Fibers” R. S. Asquith ed., Plenum Press, New York (1977), pp. 147–191.
3. 4) R. D. B. Fraser, J. M. Gillespie, T. P. MacRae, and R. C. Marshall, presented at the Proceedings of the 7th International Wool Textile Research Conference, Tokyo II (1985), pp. 36–44.
4. 5) J. M. Gillespie, “Cellular and Molecular Biology of Intermediate Filaments”, R. D. Goldman and P. M. Steinert eds., Plenum Press, New York, London (1990), pp. 95–128.