SIMBAD references

We have used the Effelsberg 100-meter telescope to map the 36GHz 4_–1->3₀E methanol transition in galactic star forming regions where methanol masers were previously detected. In most sources, the emission consists in one or several narrow (maser) features superimposed on a broader, presumably quasi-thermal component. The line shapes and positions of the narrow features are often similar to those observed in the other ClassI methanol maser transitions (at 25, 44, 84 and 95GHz), but with some exceptions. Our observations confirm that, unlike the strong ClassII methanol masers (at 12.2, and 6.6GHz), the ClassI methanol masers are offset from the compact HII regions, infrared sources and OH/H₂O masers. In outflow sources, these are located at the edge of the molecular lobes.