@article{4228,
      author       = "Simonsen, O. and International Union of Geodesy and
                      Geophysics - XII General Assembly Helsinki 25 July - 6
                      August 1960",
      title        = "Closing errors for a part of U.E.L.N. comprising CH + D +
                      DK + I + NL and small parts of A and F (polygons 2001 -
                      2011, 5001 - 5003, 9001 - 9002, 9011, 9012, 9014,and parts
                      of polygons 9003, 9005, 9006, 9007, 9008, 9009, 9010, 9013,
                      9015 - 9019 and some single lines within I) calculated by
                      the use of both (a) true gravity g at ground surface (b)
                      theoretical standard gravity in zero level  ",
      year         = "1960",
      note         = "1 sv.International Association of Geodesy International
                      Commission for European Levelling",
}