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WikiPedia: HE0450-2958 http://nedwww.ipac.caltech.edu/ http://adsabs.harvard.edu/abs/2005Natur.437..381M http://adsabs.harvard.edu/abs/2006MNRAS.367.1746M http://adsabs.harvard.edu/abs/2007AJ....133..432Z http://adsabs.harvard.edu/abs/2007ApJ...658..107K http://adsabs.harvard.edu/abs/2007ApJ...662..872F http://aladin.u-strasbg.fr/AladinPreview?-c=04+52+... http://www.aanda.org/10.1051/0004-6361/200912848/p... http://arxiv.org/abs/astro-ph/0511242 http://arxiv.org/abs/astro-ph/0511245