Unlocking the potential of the XMM Serendipitous Survey via multi-colour broad band imaging Yuan, W. ; McMahon, R. G. ; Watson, M. ; Tedds, J. ; Motch, C. ; Schwope, A. ; XMM Survey Science Center Team Abstract Publication: Astronomische Nachrichten Pub Date: 2003 DOI: 10.1002/asna.200310077 Bibcode: 2003AN....324..178Y