Based on observations collected at the University of Toronto Southern Observatory, Las Campanas, Chile, and the Complejo Astronómico El Leoncito, (CASLEO), Argentina, operated under agreement between the Consejo Nacional de Investigaciones Científicas y Técnicas de la República Argentina and the National Universities of La Plata, Córdoba and San Juan.

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Table 1 is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via
http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/371/908.

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...ázquez

Member of the Carrera del Investigador Científico, CONICET.

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... Baume

Post-doctoral fellow of CONICET.

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