Excess molar enthalpies, H-m(E), at 298.15 K and atmospheric pressure were measured for {x(1) (CH3(CH2)(3))(3)O + x(2) CH3(CH2)(2)OH + (1 - x(1) - x(2)) CH3(CH2)(6)CH3} and the corresponding binary mixtures, with a Calvet microcalorimeter. The H-m(E) values for all the mixtures were positive. Variable-degree polynomials have been fitted to the results.