1. Landolt and Börnstein (1981) Numerical data and functional relationships in science and technology; Ferroelectric and related substances a: oxides, Springer-Verlag Berlin
2. Lines, M.E. and Glass (1977), A.M., Principle and applications of ferroelectric and related materials, Clarendon, Oxford
3. Vugmeister B.E. and Glinchuk (1980) M.D. Some features of the cooperative behaviour of paraelectric defects in strongly polarizable crystals Sov.Phys.JETP 52, 482–484
4. Maglione M. (1992) Experimental evidence for a local disorder in pure and doped perovskites, Ferroelectrics 137, 113–122
5. Cross L.E. (1987), Relaxor ferroelectrics Ferroelectrics 76, 241