References
- Smolenskii , G. A. , Bokov , V. A. , Isupov , V. A. , Krainik , N. N. , Pasynkov , R. E. and Sokolov , A. I. 1984 . Ferroelasrics and Related Materials , New York : Gordon and Breach Publ. .
- Dvorak , V. 1970 . J. Phys. Soc. Japan, Suppl. , 28 : 252
- Levanjuk , A. P. and Sannikov , D. G. 1974 . Uspekhi Fiz. Nauk , 112 : 561 (in Russian)
- Toledano , J. C. and Toledano , P. 1987 . The Landau Theory of Phase Transitions , World Scientific Publishing. Co. Pte Ltd. .