An extremely primitive halo star

  title={An extremely primitive halo star},
  author={Elisabetta Caffau and Piercarlo Bonifacio and Pierluigi Monaco and Monique Spite and F. Spite and Hans-G. Ludwig and Roger. Cayrel and Simone Zaggia and François Hammer and Sofia Randich and Paolo Molaro and V. Hill ZAH-LSW Heidelberg and Gepi - Obs. de Paris and Cnrs and Univ. Paris Diderot and Universit'e de Picardie Jules Verne and Max-Planck-Institut fur Astrophysik and Eso - Santiago and INAF-Osservatorio astronomico di Padova and Inaf - Arcetri and INAF-Osservatorio Astronomico di Trieste and Universit'e de Nice Sophia Antipolis and Oca and Laboratoire Cassiop'ee},
Zentrum für Astronomie der Universität Heidelberg, Landessternwarte, Königstuhl 12, 69117 Heidelberg, Germany GEPI, Observatoire de Paris, CNRS, Université Paris Diderot, Place Jules Janssen, 92190 Meudon, France UPJV, Université de Picardie Jules Verne, 33 Rue St Leu, F­80080 Amiens Max­Planck Institut für Astrophysik, Karl­Schwarzschild­Str. 1, 85741 Garching, Germany European Southern Observatory, Casilla 19001, Santiago, Chile Istituto Nazionale di Astrofisica, Osservatorio Astronomico di… 

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