We would like to thank Dr. M. Politano who made his population calculations available in a machine-readable form. MPD thanks for the hospitality at the Astrononomisches Institut Münster during his stay there and for the financial support of DAAD/CAPES (grant No. 415-WA-BR). AB is grateful for the hospitality found at the LNA/CNPq.
© European Southern Observatory (ESO) 1997
Online publication: June 5, 1998