@Article{baumgartner-etal:99,
  author =       "Albert Baumgartner and Carsten Steger and Helmut
                  Mayer and Wolfgang Eckstein and Heinrich Ebner",
  title =        "Automatic Road Extraction Based on Multi-Scale,
                  Grouping, and Context",
  journal =      "Photogrammetric Engineering \& Remote Sensing",
  year =         "1999",
  volume =       "65",
  number =       "7",
  pages =        "777--785",
  month =        jul
}