We would like to thank Drs. Marcus Price and Ian Stewart for help with the observations at Parkes. We also thank Dr. Roland Gredel for help with the NTT observations at La Silla, that were performed in Director's Discretionary Time. We thank Dr. Anita Richards for helpful discussions, and an anonymous referee for her/his remarks that helped improve the paper. This research was partly supported by the NWO under Pionier Grant 600-78-333. O jacco agradece ao anjinho Joana por ser para ele como ele queria ser para ela.
© European Southern Observatory (ESO) 1998
Online publication: August 6, 1998