Table 2 is only available in electronic form at http://www.aanda.org

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Present address: Integral Science Data Centre, Ch. d'Ecogia 16, 1290 Versoix, Switzerland & Geneva Observatory, Ch. des Maillettes 51, 1290 Sauverny, Switzerland.

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... stars

The abundances used, relative to the solar abundances by Anders & Grevesse (1989), are: C = 0.45, N = 0.788, O = 0.426, Ne = 0.832, Mg = 0.263, Al = 0.5, Si = 0.309, S = 0.417, Ar = 0.55, Ca = 0.195, Fe = 0.195, and Ni = 0.195.

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