Voges, W. High Energy Astrophysics, MPI for Extraterrestrial Physics, Max Planck Society;
Zickgraf, F.-J., Engels, D., Hagen, H.-J., Reimers, D., & Voges, W. (2003). The Hamburg/RASS Catalogue of optical identifications. Northern high-galactic latitude ROSAT Bright Source Catalogue X-ray sources. Astrophysics & Astronomy, 406: DOI: 10.1051/0004-6361:20030679, pp. 535-553.