@inproceedings{dondrup2014social,
  title={Social distance augmented qualitative trajectory calculus for Human-Robot Spatial Interaction},
  author={Dondrup, Christian and Bellotto, Nicola and Hanheide, Marc},
  booktitle={2014 RO-MAN: The 23rd IEEE International Symposium on Robot and Human Interactive Communication},
  pages={519--524},
  year={2014},
  organization={IEEE}
}