... supergiants[*]
Based on observations collected at the European Southern Observatory, Chile (ESO N$^{\circ}$ 62.H-0176). 
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...[*]
Appendix A is only available in electronic form at http://www.edpsciences.org 
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... [M/H][*]
Using the usual logarithmic notations $[X]=\log \varepsilon (X)_{\star} - \log \varepsilon (X)_{\odot}$, with $\log \varepsilon(X)=\log (N_{X} / N_{\rm H}) + 12$, the $\varepsilon (X)$ being the abundance of element X and the Ni number densities. 
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Copyright ESO 2006