Isothermal (vapor + liquid) equilibria of maleic anhydride + di-isobutyl hexahydrophthalate and maleic anhydride + di-n-butyl phthalate systems at T = (413.2, 433.2 and 453.2)K Yin, L.; Liu, Z.; Tian, Y.; Zhu, H.; The Journal of Chemical Thermodynamics 2006, 38, 983-987