Vatulyan, Alexander Ovanesovich, and Vladimir Vladimirovich Dudarev. “On Reconstruction of Inhomogeneous Properties of Piezoelectric Solids”. Computational Continuum Mechanics, vol. 5, no. 3, Oct. 2012, pp. 259-64, https://doi.org/10.7242/1999-6691/2012.5.3.30.