Title: Long-term variability of AGN at hard X-rays
Authors: Soldi, S.; Beckmann, V.; Baumgartner, W. H.; Ponti, G.; Shrader, C. R.; Lubiński, P.; Krimm, H. A.; Mattana, F.; Tueller, J.
Journal: A&A
Publication type: article
DOI: 10.1051/0004-6361/201322653