| Abstract | We present 21-cm HI measures of four galaxies, with flux densities calibrated to 7-9% relative to the scale of secondary continuum standards listed by Baars et al. (t977). Because of their small size, narrow line widths and relatively large signal strengths, these galaxies are suitable as line calibrators for other telescopes, especially when frequency-switching receivers are used. Key words: galaxies - 21-crn radiation - observational methods |
