Moment zero maps of four selected lines for four sources included in Fig. 1. The line, name of the source and E_up of the line are printed in white at the middle top of each panel. The beam is also shown on the bottom left of each panel. The continuum contours are shown in black and are at [3, 5, 10, 20, 30]σ_cont with σ_cont for the sources from top to bottom being 7.6, 4.1, 1.9 and 0.8 mJy beam⁻¹, respectively. The scale bars on the bottom right of each panel from top to bottom show lengths of 10942, 7199, 11518, and 39089 au at the distances of the sources.