Astronomy and Astrophysics
['The Hamburg/RASS Catalogue of optical identifications. Northern high-galactic latitude ROSAT Bright Source Catalogue X-ray  sources', 'The Hamburg/RASS Catalogue of optical identifications. Northern high-galactic latitude ROSAT Bright Source Catalogue X-ray  sources', 'ROSAT', 'English', 'Astronomy and Astrophysics']