The Qualitative Treatment of Spatial Data. - Kazuko Takahashi; Takao Sumitomo (Int. J. Artif. Intell. Tools, 2007)

On Embedding a Qualitative Representation in a Two-Dimensional Plane. - Kazuko Takahashi; Takao Sumitomo; Izumi Takeuti (Spatial Cogn. Comput., 2008)