$a Physics of star formation in galaxies : Saas-Fee Advanced Course 29, lecture notes 1999, Swiss Society for Astronomy and Astrophysics / F. Palla, H. Zinnecker. - Berlin, 2002. $b Red. ; CIP LCC (G. Meynet) ; (Observatoire de Genève, Ch. des Maillettes, 51, CH-1290 Sauverny, Switzerland)