Published online by Cambridge University Press: 25 May 2016
We present first results of the Hamburg/SAO Survey of emission-line galaxies (hereafter HSS, SAO—Special Astrophysical Observatory, Russia) initiated to search for extremely metal-deficient (Z < Z⊙/10) galaxies and to create a large sample of Blue Compact Galaxies (BCG). This “Northern BCG Sample,” will be assembled by merging the HSS with samples from the Second Byurakan Survey (SBS) (Stepanian et al. 1987) and the Case Low-Dispersion Northern Sky Survey (Pesch et al. 1991).