Goethite as an alternative origin of the 3.1 μm band on dark asteroids (Corrigendum) P. Beck, E. Quirico, D. Sevestre, G. Montes-Hernandez, A. Pommerol and B. Schmitt A&A, 530 (2011) C2 Published online: 11 May 2011 DOI: 10.1051/0004-6361/201015851e