Left panel: ratio between the zero moment of the CH₃OH ﹩({{\rm{E}}}_{2})\,\,{J}_{{K}_{a}{K}_{c}}={5}_{-\mathrm{1,0}}\to {4}_{\mathrm{0,0}}﹩ and (E₁) ﹩{2}_{\mathrm{1,1}}\to {1}_{\mathrm{1,0}}﹩ lines. Right panel: zero moment of the CH₃OH ﹩({{\rm{E}}}_{2})\,\,{J}_{{K}_{a}{K}_{c}}={5}_{-\mathrm{1,0}}\to {4}_{\mathrm{0,0}}﹩ emission. The three masers (yellow circles) correspond to the three strongest sources (whose coordinates are given in Table 2), conspicuous even in the logarithmic color stretch. Red crosses and numbers show continuum 3 mm sources near the masers.