The spectra reduction software of Dr. M. Stickel was used. We deeply appreciate the very helpful support by the staff of Calar Alto and La Silla observatories during numerous observation runs. It is also a pleasure to thank for the important work done by the people of the NED database. We gratefully acknowledge the discussions with Drs. R. Bender, S. Puls'nitz, J. Einasto and J. Salzer. Finally we wish to express our sincere thanks to Dr. A. P. Fairall as referee for his immediate reaction and his useful remarks.
© European Southern Observatory (ESO) 1997
Online publication: July 8, 1998