1. M. E. Lines and A. M. Glass, Principles and Applications of Ferroelectrics and Related Materials (Clarendon, Oxford, 1977), Chap. 9, p. 293.
2. Ferroelectricity of Perovskites under Pressure
3. Ab initiostudies on high pressure phases of ice
4. Ferroelectricity of Glycine Sulfate
5. F. Jona and G. Shirane, Ferroelectric Crystals (Pergamon, Oxford, London, 1962), Chap. 2, p. 28.