¹³CH₃OH 10_(0,10)→9_(1,8) transition at 302.590 GHz (indicated by dash-dotted lines) detected towards each region. Frequencies are shifted to the rest frame of the individual regions. Green lines represent the modelled spectra of ¹³CH₃OH without blending, i.e., excluding the contribution from CH₃OCHO (including the contribution from CH₃OCHO does not change the ¹³CH₃OH column density of the best-fit model). Yellow lines represent the modelled spectra of CH₃OCHO and magenta lines represent the sum of the ¹³CH₃OH and CH₃OCHO spectra.