1. Human hair form. Morphology revealed by light and scanning electron microscopy and computer aided three-dimensional reconstruction
2. SL Moshella, and HJ Hurley, Dermatology .Philadelphia:W.B. Saunders,1985 .
3. H Pinkus, W Montagna, and RA Ellis, Embryology of hair . In:eds.Embryology of hair .New York:Academic Press,1958 ,1 –32 .
4. U Drews, Color Atlas of Embryology .Stuttgart:George Thieme Verlag,1995 ,194 –6 .