Color map of G37.55+0.20 representing the SiO 86.846 GHz line, overlaid with the H₂CO line at 89.188 GHz (grey contours, with the first level 15 times the 4.3 mJy beam⁻¹ rms and steps equal to that value), and the C¹⁷O line at 336.6291 GHz (deep-pink contours, with the first level at 2.1 mJy beam⁻¹ and 1.6 mJy beam⁻¹ steps). All data were obtained from the ALMA archive. The maximum of the C-band continuum with JVLA is represented with an orange star (Araya et al. 2007). The H₂CO maser emission at 4.83 GHz is represented with a magenta cross (Araya et al. 2005). The black triangles represent the positions of the 22 GHz water masers, as observed by JVLA (Beuther et al. 2002b). The Finlay 6.7 GHz methanol maser emission from this work is represented by green circles.