Tables 1 to 6 and 8 to 17 are only available in electronic form at http://www.edpsciences.org, Table 7 is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via
http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/366/508 Figures 2-10, 12, 14, 15, 17-19 are only available in electronic form at http://www.edpsciences.org, see Note added in proof

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Note that in this paper, we misinterpreted Stothers & Chin's (1996) concept of the "optically thick ejected cloud'' in point 4 of their conclusions. They expressed the view that the observable changes in the photometric characteristics are primarily produced by the optically thick cloud, as part of the expanding and contracting stellar envelope, if the latter does not become fully detached. According to them, the amount of mass loss may be even not much influenced during the instability cycles.

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... 1995

In the latter paper the cause of the anti-correlation between the H $\beta$ index and the continuum light should probably sought in the S Dor star and not in the excistence of an extended HII region. When the S Dor star becomes fainter by the microvariations, the H $\beta$ emission becomes obviously stronger.

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