Institution: | Departamento de Astrofísica, Facultad de Físicas, Universidad Complutense, E-28040 Madrid, Spain;NASA/IPAC Extragalactic Database, California Institute of Technology, MS 100-22, Pasadena, CA 91125, USA;Steward Observatory, The University of Arizona, Tucson, AZ 85721, USA;School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD |