@article{BittnerStell2002,
  author	= {Bittner, Thomas and Stell, John G.},
  URL		= {http://people.ifomis.uni-leipzig.de/thomas.bittner/BittnerStellSCC.ps},
  ps		= {http://people.ifomis.uni-leipzig.de/thomas.bittner/BittnerStellSCC.ps},
  title		= {Approximate qualitative spatial reasoning},
  journal	= {Spatial Cognition and Computation},
  volume	= {2},
  year		= {2002},
  number	= {4},
  pages		= {435--466}
}