@inproceedings{ijcai2007p146,
  title     = {r-grams: Relational Grams},
  author    = {Landwehr, Niels and de Raedt, Luc},
  booktitle = {Proceedings of the Twentieth International Joint Conference on
               Artificial Intelligence, {IJCAI-07}},
  publisher = {International Joint Conferences on Artificial Intelligence},
  editor    = {Ramon López de Mántaras},
  pages     = {907--911},
  year      = {2007},
  url       = {https://ijcai.org/proceedings/2007/146},
}