Sub arcsec evolution of solar magnetic fields Th. Roudier, J. M. Malherbe, J. Moity, S. Rondi, P. Mein and Ch. Coutard A&A, 455 3 (2006) 1091-1098 Published online: 16 August 2006 DOI: 10.1051/0004-6361:20064963