Early-type stars in the core of the young open cluster Westerlund 2 G. Rauw, J. Manfroid, E. Gosset, Y. Nazé, H. Sana, M. De Becker, C. Foellmi and A. F. J. Moffat A&A, 463 3 (2007) 981-991 Published online: 19 December 2006 DOI: 10.1051/0004-6361:20066495