Two years of INTEGRAL monitoring of the soft gamma-ray repeater SGR 1806-20: from quiescence to frenzy

D. Gotz, S. Mereghetti, S. Molkov, K. Hurley, I.F. Mirabel, R. Sunyaev, G. Weidenspointner, Søren Kristian Brandt, M. Del Santo, M. Feroci, E. Gogus, A. von Kienlin, M. van der Klis, C. Kouveliotou, Niels Lund, G. Pizzichini, P. Ubertini, C. Winkler, P.M. Woods