Long-term spectropolarimetric monitoring of the cool supergiant betelgeuseI. Bedecarrax, P. Petit, M. Aurière, J. Grunhut, G. Wade, A. Chiavassa, J.-F. Donati, R. Konstantinova-Antova and G. PerrinEAS Publications Series, 60 (2013) 161-165DOI: https://doi.org/10.1051/eas/1360018