Spectropolarimetric multi line analysis of stellar magnetic fields J. C. Ramírez Vélez, M. Semel, M. Stift, M. J. Martínez González, P. Petit and N. Dunstone A&A, 512 (2010) A6 Published online: 18 March 2010 DOI: 10.1051/0004-6361/200810484