@article{12768,
      author       = "Hallert, B. and 8th International Congress of
                      Photogrammetry, Stockholm, 1956",
      title        = "The influence of radial distortion and other systematic
                      errors upon photogrammetric models from approximately
                      vertical pictures  ",
      year         = "1956",
      note         = "1 sv., Communication of the Commission II. Zvl. ot. z
                      čas.:Svensk Lantmäteritidskrift, 1956, Congress Number",
}