ASAS Photometry of ROSAT Sources. II. New Variables from the ASAS North Survey

We present a catalog of 307 optical counterparts of the bright ROSAT X-ray sources, identified with the ASAS North survey data and showing periodic brightness variations. They all have declination north of -25°. Other data available from the literature for the listed stars are also included. All the tabulated stars are new variables, except for 13 previously known, for which the revised values of periods are given.