Solutions of Urea and Tetramethylurea in Formamide and Water: A Comparative Analysis of Volume Characteristics and Solute-Solute Interaction Parameters at Temperatures from 288.15 to 328.15 K and Ambient Pressure Ivanov, E.V.; Kustov, A.V.; Lebedeva, E.Y.; Journal of Chemical & Engineering Data 2019, 64, 5886-5899