@article{Lampens:2380,
      author        = "Lampens, P. and  Cuypers, J. and  Oblak, E. and 
                       Seggewiss, W. and  Duval, D.",
      title         = "{Accurate CCD Photometry and Astrometry for HIPPARCOS
                       Visual Double Stars}",
      year          = "1997",
}