@article{SchifferFerreinLakemeyer2011,
  author    = {Stefan Schiffer and Alexander Ferrein and Gerhard Lakemeyer},
  title     = {Reasoning with Qualitative Positional Information for Domestic Domains in the Situation Calculus},
  journal   = {Journal of Intelligent \& Robotic Systems},
  volume    = {63},
  number    = {2},
  pages     = {273 -- 300},
  year      = {2011},
}