@article{8939,
      author       = "Ihde, J. and Schlueter, W. and Adam, J. and Gurtner, W. and
                      Harsson, B.G. and Woeppelmann, G. and EUREF-Symposium,
                      Sofia, 1997",
      title        = "European vertical reference Network 97 GPS campaign
                      (EUVN97). Report to the EUVN Working group  ",
      year         = "1997",
      note         = "1 sv.",
}