Based on spectroscopic observations collected at the European Southern Observatory (ESO), within the Observatório Nacional ON/ESO and ON/IAG agreements, under FAPESP project No. 1998/10138-8. Photometric observations collected at the Observatório do Pico dos Dias (LNA/MCT).

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Full Tables 2 and 6 are 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/454/917

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...

Figures 18 to 21 and Tables 4, 5, 7 and 8 are only available in electronic form at http://www.edpsciences.org

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... Allen

Present address: Observatório do Valongo/UFRJ, Ladeira do Pedro Antonio 43, 20080-090 Rio de Janeiro, RJ, Brazil.

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