The temperature dependence of the viscosity of inorganic glasses in the glass transition region is successfully described by the Williams--Landel--Ferry (WLF) equation. For the studied glasses, the value of f_g=1/C1 weakly depends on the nature of the glasses. There is a linear correlation between delta delta Tg and Tg. From the data on the parameters of the WLF equation C1 and C2, we calculated delta delta Tg, as well as the relaxation time of the structure taug at the glass transition temperature of the glasses under study. Keywords: Viscosity in the glass transition region, Williams--Landel--Ferry equation, kinetic glass transition criterion, chalcogenide glasses, fluctuation volume fraction, liquid--glass transition.

The Belomestnykh--Tesleva's formula is interesting in that it establishes an unambiguous relationship between the Poisson's ratio and the Gruneisen's parameter. The derivation of this formula from the generally accepted Gruneisen's equation is discussed. The Belomestnykh--Tesleva's formula, obtained earlier from other assumptions, is derived using the theory of elasticity and the Leontiev's equation. For a number of silicate glasses and glassy metaphosphates of alkaline earth metals, the proposed approach finds a fairly satisfactory agreement with the experimental data. Keywords: Gruneisen's equation, Gruneisen's parameter, Poisson's ratio, shear modulus, isothermal bulk modulus, acoustic wave velocities.