@article{Helt:1904,
      author        = "Helt, B. E. and  Bibo, E. A. and  Cuypers, J. and 
                       Debehogne, H. and  de Campos, J. A. and  Franco, G. A. P.
                       and  Gimenez, A. and  Gray, R. O. and  Lindgren, H. and 
                       Lundstrom, I. and  Manfroid, J. and  Ng, Y. K. and  Olsen,
                       E. H. and  Pernier, B. and  Petersen, C. S. and  Vaz, L. P.
                       R. and  Verschueren, W.",
      title         = "{Stromgren six-colour photometry of SN 1987 A. I - Days 1
                       to 330}",
      year          = "1991",
}