Thermodynamic properties of the AgGaGe3Se8 compound at T≤500 K determined by the emf method - M. Moroz; P. Demchenko; M. Prokhorenko; B. Rudyk; L. Soliak; O. Mysina; O. Pereviznyk; O. Reshetniak (Proceedings of the Shevchenko Scientific Society : Shemical Sciences, 2022)