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CCD photometry of resolved dwarf irregular galaxies was obtained with the 4-m Cerro Tololo Interamerican Observatory telescope in February 1985. BV data from 77 stars in DDO 187 are used to infer a distance modulus of 28.2 + or - 0.6, placing this galaxy out of the Local Group, at a distance of 4.4 + or - 1.0 Mpc. In the second part, UBV photometry

The authors present CCD UBV photometry of 142 resolved stars in the Local Group dwarf irregular galaxy GR 8. Its distance modulus has been found to be 25.0. The luminosity function has been derived. The percentage of the total luminosity in stars brighter than MV = -2 is found to be about 30%. The derived differential (IMF) for stars with masses

Two EXOSAT observations of gamma-ray burst error boxes and their possibly associated optical transients are discussed. No point source was detected in either box. A comparison with Einstein data (Pizzichini et al., 1986) is made for one of them (November 19, 1978). The data are interpreted in the framework of neutron star models for gamma-ray

Spectroscopic and photometric observations are used to determine the distributions of gas and the kinematics in the central zones of a number of spirals. In addition to a ring structure in the gas, there is often found a measurable expansion with high radial velocity near the nucleus. A significant correlation is noted between the absence of