Na, Mg and Al abundances as a population discriminant for nearby metal-poor stars T. Gehren, J. R. Shi, H. W. Zhang, G. Zhao and A. J. Korn A&A, 451 3 (2006) 1065-1079 Published online: 04 May 2006 DOI: 10.1051/0004-6361:20054434