Search for H2O masers at high velocities compared to the averaged velocity of the emission was carried out using the Haystack antenna (36m diameter) from several star forming region (1981 RMxAA, 5, 87)[2].

The best maps of the H2O maser emission from W49(N) were produced using VLBI techniques. We detected over 386 different spectral features in space and velocity (1982 ApJ, 255, 128)[3]