Zhang Li-Juan, Wang Li-Hai, Liu Jian-Dang, Li Qiang, Cheng Bin, Zhang Jie, An Ran, Zhao Ming-Lei, Ye Bang-Jiao. Positron annihilation spectrum study in non-ferroelectric piezoelectricity SrTiO3-Bi12TiO20 (ST-BT) composite ceramicsJ. Acta Physica Sinica, 2012, 61(23): 237805. DOI: 10.7498/aps.61.237805