The (liquid + liquid) equilibria of {x(1)CH(3)CN + x(2)C(2)H(5)OH + (1-x(1)-x(2))C7H16} and {x(1)CH(3)CN + x(2)CH(3)(CH2)(2)OH + (1-x(1)-x(2))C7H16} at the temperature T = 313.15 K, and {x(1)C(6)H(5)NH(2) + x(2)CH(3)OH + (1-x(1)-x(2))c-C6H12} at T = 298.15 and T = 300.15 K have been measured. At T = 298.15 K the last mixture has only one region of immiscibility, while at T = 300.15 K the mixture has two separate biphasic regions. The experimental values have been compared with those predicted with the modified UNIQUAC and extended UNIQUAC models having only binary parameters.