Non-thermal radio emission from O-type stars - I. HD 168112 R. Blomme, S. Van Loo, M. De Becker, G. Rauw, M. C. Runacres, D. Y. A. Setia Gunawan and J. M. Chapman A&A, 436 3 (2005) 1033-1040 Published online: 03 June 2005 DOI: 10.1051/0004-6361:20042383