The discovery of hard X-ray emission in the persistent flux of the Rapid Burster M. Falanga, R. Farinelli, P. Goldoni, F. Frontera, A. Goldwurm and L. Stella A&A, 426 3 (2004) 979-983 Published online: 18 October 2004 DOI: 10.1051/0004-6361:20041243