Large panels: observed CH₃OH (top panel) and CH₃CN (bottom panel) lines toward core A in G35.20−0.74 N. The red line shows the best fitted obtained by myXCLASS (see Sect. 4.1). The fit in the top panel includes ground state CH₃OH and ¹³CH₃OH and torsionally excited CH₃OH lines, while the fit in the bottom panel includes ground state CH₃CN and CHCN and vibrationally excited CH₃CN lines in the frequency ranges shown in the panels. Small panels: χ² values obtained from the fits minimization. From left to right the panels show the size, the temperature, the column density, the linewidth and the LSR velocity.