Possible detections (we note that only the first four spectra are shown here; the full set is available in Appendix B). Shown is the flux density of the 21-cm H I line emission, S_HI, in Jy, as a function of the radial velocity in the LSR reference frame, V_LSR, in km s⁻¹. The peak profiles (see Section 3.2) are indicated by a solid black line, while the total profiles (which could only be determined for GY Aql and U CMi) are indicated by a dashed black line. The Gaussians fitted to the profiles are shown as blue lines, solid for fits to the peak profiles and dashed for fits to the total profiles. Spectra are shown for all 21 objects with possible H I detections (see Table B.4). The vertical black lines indicate the centre velocity of our Gaussian fit to the peak H I profile (or, if available, to the total H I profile), the red vertical and horizontal lines show respectively the central CO or OH line velocity from the literature and its corresponding expansion velocity, whereas green lines indicate other types of literature velocities (e.g. optical or SiO lines) and an indicative expansion velocity of 10 km s⁻¹, that is, the average measured value. The flat blue horizontal lines show the 0 Jy flux density level. The plotted total velocity range of the spectra is 60 km s⁻¹, except for the 80 km s⁻¹ range used for RAFGl 3099 due to its broad profile.