1. P.G. de Gennes: The Physics of Liquid Crystals ( Clarenden Press, Oxford, 1974 ).
2. S. Chandrasekhar:Liquid Crystals ( Cambridge University Press, Cambridge, 1977 ).
3. Xie Yu-Zhang: The Physics of Liquid Crystals ( Science Press, Beijing, 1988 ).
4. L. Lam and C.Q. Shu: in Nonlinear Mechanics, edited by Chien Wei-Zang ( World Scientific, Singapore, 1986 ).
5. F.M. Leslie: in Advances in Liquid Crystals, Vol. 4, edited by G.H. Brown ( Academic, New York, 1979 ).