First detections of extragalactic SO2, NS and NO S. Martín, R. Mauersberger, J. Martín-Pintado, S. García-Burillo and C. Henkel A&A, 411 2 (2003) L465-L468 Published online: 17 November 2003 DOI: 10.1051/0004-6361:20031442