1. Ivanova, L. A. and Venevtsev, Yu. N. 1983.Forecast of ferroelectrics science and technology (ferroelectricantiferroelectric and related compounds)99Moscow in Russian
2. Shebanov, L. A. 1974.The Phase Transitions in Ferroelectrics with the Perovskite-like Structure, 150–160. Riga: Latvian State University. in Russian