Mixing thermodynamic properties of 1-butyl-4-methylpyridinium tetrafluoroborate [b4mpy][BF4] with water and with an alkan-1ol (methanol to pentanol) Ortega, J.; Vreekamp, R.; Penco, E.; Marrero, E.; The Journal of Chemical Thermodynamics 2008, 40, 1087-1094