Excess molar volumes of {x(1)di-n-butyl ether+x(2)1-pentanol+(1-x(1)-x(2))n-dodecane} and the binary mixtures {xdi-n-butyl ether+(1-x)n-dodetane} and {x1-pentanol+(1-x)n-dodecane} were measured at 298.15 K using an Anton Paar DMA 60/602 densimeter. All the experimental values were compared with the results obtained by empirical expressions for estimating ternary properties from binary results. Variable-degree polynomials have been fitted to the results. The experimental excess molar volumes were compared with the results obtained with the Nitta-Chao model.