High-Pressure Phase Behavior of Systems with Ionic Liquids: Part IV. Binary System Carbon Dioxide + 1-Hexyl-3-methylimidazolium Tetrafluoroborate Costantini, M.; Toussaint, V.A.; Shariati, A.; Peters, C.J.; Kikic, I.; Journal of Chemical & Engineering Data 2005, 50, 52-55