Knowledge Discovery in Large Spatial Databases: Focusing Techniques for Efficient Class Identification.

http://dx.doi.org/10.1007/3-540-60159-7_5 Martin Ester Hans-Peter Kriegel Xiaowei Xu Knowledge Discovery in Large Spatial Databases: Focusing Techniques for Efficient Class Identification. 67-82 SSD/1995/P067.pdf 1995 conf/ssd/95 SSD db/conf/ssd/ssd95.html#EsterKX95