Measurement of the mass distributions in the decays $D^0\to K^-\pi^+\pi^0$, $D^0\to K^0_S\pi^+\pi^-$, $D^+\to K^0_S\pi^+\pi^0$ and $D^+\to K^-\pi^+\pi^+$. The data were read from the plots in the paper. Resolution/acceptance effects have been not unfolded and given the agreement with the model in the paper this analysis should only be used for qualitative studies.