Density and Speed of Sound of Binary Mixtures of N-Methyldiethanolamine and Triethanolamine with Ethanol Álvarez, E.; Gómez-Díaz, D.; La Rubia, M.D.; Navaza, J.M.; Pacheco, R.; Sánchez, S.; Journal of Chemical & Engineering Data 2007, 52, 2059-2061