Observed protostellar spectra that we were able to reproduce with rotationally broadened stellar photospheric profiles. Right panel: overplotted are some synthetic spectra (with a fixed T_eff of 3649 K) (solid lines) with different vsini rotations with the spectrum of the protostar GY23 on one of the dates it was observed. Left panel: the same, but with a fixed vsini of 17 km s^-1 and different temperatures.