uvby-β photometry of high-velocity and metal-poor star. VIII. Stars of very low metal abundanceW. J. Schuster, P. E. Nissen, L. Parrao, T. C. Beers and L. P. OvergaardAstron. Astrophys. Suppl. Ser., 117 2 (1996) 317-334DOI: https://doi.org/10.1051/aas:1996102