@article{vanLoo:1988,
      author        = "van Loo, S. and  Blomme, R. and  Dougherty, S. M. and 
                       Runacres, M. C.",
      title         = "{Non-thermal radio emission from O-type stars. III. Is
                       Cygnus OB2 No. 9 a wind-colliding binary?}",
      year          = "2008",
}