@article{TimpfFrank1997,
  author    = {Sabine Timpf and Andrew U. Frank},
  title     = {Using hierarchical spatial data structures for hierarchical spatial reasoning},
  journal   = {Lecture Notes in Computer Science},
  volume    = {1329},
  pages     = {69 -- 83},
  doi       = {10.1007/3-540-63623-4_43},
  year      = {1997},
}