Lars Kulik, Alexander Klippel. Reasoning about Cardinal Directions Using Grids as Qualitative Geographic Coordinates. In Christian Freksa, David M. Mark, editors, Spatial Information Theory: Cognitive and Computational Foundations of Geographic Information Science, International Conference COSIT 99, Stade, Germany, August 25-29, 1999, Proceedings. Volume 1661 of Lecture Notes in Computer Science, pages 205-220, Springer, 1999. [doi]
Abstract is missing.