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Starbursts are thought to be the result of gas accretion toward the central regions of galaxies. There are mainly two mechanisms known which can transport mass into this region: either tidal interactions or bars (see e.g., Combes 1988). I suggest that the broad HI absorption lines in the central region of most luminous spirals (see Table 1) are caused by a fast-rotating ring of cold gas. The accretion of gas in the inner region (probably near the inner Lindblad resonances) could have been induced by the bar potential of these galaxies (see e.g., Combes & Gerin 1985). Since outflow of gas from the central region is another phenomenon observed in this group of galaxies I propose a model in which the neutral gas is fuelling the nuclear starburst where it is partly ionized and then ejected by supernova explosions and stellar winds (see Section 5).