Left panel: view of the CH₃OH maser features detected around IRAS 06058+2138-NIRS 1 (Table A.1). Triangles symbols identify CH₃OH maser features scaled logarithmically according to their peak flux density (Table A.1). Maser LSR radial velocities are indicated by color (the assumed velocity of the YSO is km s^-1, Saito et al. 2007). A 4 Jy beam^-1 symbol is plotted for illustration. The linear polarization vectors, scaled logarithmically according to polarization fraction P_l, are overplotted. On the right-bottom corner the error weighted orientation of the magnetic field (Φ_B, see Sect. 6.2.1) is also reported, the two dashed segments indicates the uncertainty. The two arrows indicate the direction of the red- and blue-shifted lobe of the bipolar outflow (PA_out = 130°; Wu et al. 2010). The dashed line is the best linear fit of the CH₃OH maser features of group A (PA_CH3OH = 78° ± 7°). Right panel: zoom-in view of group A.