Exploring the origin of magnetic fields in massive stars: a survey of O-type stars in clusters and in the field
S. Hubrig, M. Schöller, N. V. Kharchenko, N. Langer, W. J. de Wit, I. Ilyin, A. F. Kholtygin, A. E. Piskunov, N. Przybilla and the MAGORI collaboration
