Search for surface magnetic fields in Mira stars - First detection in χ Cygni A. Lèbre, M. Aurière, N. Fabas, D. Gillet, F. Herpin, R. Konstantinova-Antova and P. Petit A&A, 561 (2014) A85 Published online: 07 January 2014 DOI: 10.1051/0004-6361/201322826