The speed of sound in the liquid phase of hexane isomers

In this paper we measured the speed of sound over the saturation line in the liquid phase of $2$-methylpentane, $3$-methylpentane, and $2,2$-dimethylbutane using the pulse-phase echo method within a range from $-30^{\circ}$C to the critical point. The error of the obtained speed of sound is within $1$ m/s.