[1 ] Y. Saito, H. Takao and T. Tani: Nature, 2004, 432, 84.
[2 ] E. Cross: Nature, 2004, 432, 24.
[3 ] G.A. Smolenskii, V.A. Isupov and A.I. Agranovskaya: Sov. Phys. Solid State, 1961, (3) , 651.
[4 ] J. Suchanicz, K. Roleder, A. Kania and J. Hanaderek: Ferroelectrics, 1988, 77(1), 107.
[5 ] T. Takenaka, K. Maruyama and K. Sakata: Jpn. J. Appl. Phys., 1991, 30(9B), 2236.
[6 ] T.B.Wang, M. Gao, L.E. Wang, Y.K. Lu and D.P. Zhou: J. Inorg. Mater., 1987, 2(3), 223. (in Chinese)
[7 ] B.J. Chu, D.R. Chen, G.R. Li and Q.R. Yin: J. Eur. Ceram. Soc., 2002, 22, 2115.
[8 ] T. Takenaka, K. Sakata and K. Toda: Ferroelectrics, 1990, 106, 375.
[9 ] T. Takenaka, T. Okuda and K. Takegahara: Ferroelectrics, 1997, 196, 175.
[10] X.X. Wang, H.L.W. Chan and C.L. Choy: J. Am. Ceram. Soc., 2003, 86, 1809.
[11] H. Nagata and T. Takenaka: Jpn. J. Appl. Phys., 1997, 36, 6055.
[12] O. Elkechai, M. Manier and J.P. Mercurio: Phys. Status Solidi A, 1996, 157(2), 499.
[13] K. Sakata and Y. Masuda: Ferroelectrics, 1974, 7, 347.
[14] Y.W. Liao, D.Q. Xiao, D.M. Lin, J.G. Zhu, P. Yu, L. Wu and X.P. Wang: Mater. Sci. Eng. B, 2006, 133, 172.
[15] H. Nagata and T. Takenaka: J. Eur. Ceram. Soc., 2001, 21, 1299.
[16] Y.W. Liao, D.Q. Xiao, D.M. Lin, Q. Wei, Y. Zhuang, J.G. Zhu and P. Yu: Funct. Mater., 2006, 37(6), 886. (in Chinese)
[17] Q. Xu, S.T. Chen, W. Chen, S.J. Wu, J. Zhou, H.J. Sun and Y.M. Li: Mater. Chem. Phys., 2005, 90, 111.
[18] A. Herabut and A. Safari: J. Am. Ceram. Soc., 1997, 80, 2954.
[19] T. Takenaka: Ferroelectrics, 1999, 230, 87.
[20] X.X. Wang, H.L.W. Chan and C.L. Choy: Solid State Commun., 2003, 125, 395.
[21] J.S. Speck, M. Degraef, A.P. Wilkinson, A.K. Cheetham and D.R. Clarke: J. Appl. Phys., 1993, 73, 7261.