Sorokov, S. I.     Longitudinal dielectric, piezoelectric and elastic properties of the K1-x(NH4)xH2PO4 type mixed crystals. Simple model [Текст] / S.I. Sorokov, R.R. Levitskii, A.S. Vdovych, I.R. Zachek // The 36th conference of the middle european cooperation in statistical physics : progr. and abstr., 5-6 Apr. 2011, Lviv, Ukraine / Inst. for condensed matter physics, Ivan Franko nat. univ., Lviv polytechnic nat. univ. — Lviv, 2011. — P. 159.