Using delta Cep stars to study northern dwarf irregular galaxies of the Local Group .

Dwarf galaxies in the Local Group provide a unique astrophysical laboratory. Despite their proximity some of these systems still lack a reliable distance determination as well as studies of their stellar content and star formation history. We present first results of our survey of variable stars in a sample of six Local Group dwarf irregular galaxies. We describe observational strategies and data reduction, and discuss the lightcurves of newly found and rediscovered delta Cep stars in DDO 216, Leo A and GR8. Based on these data, we present newly derived independent Cepheid distances. Other variable stars found in our survey are discussed in a related article of this volume (Snigula et al.).