Hans-Peter Kriegel Peer Kröger Irina Gotlibovich Incremental OPTICS: Efficient Computation of Updates in a Hierarchical Cluster Ordering. 224-233 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2737&spage=224 2003 conf/dawak/2003 DaWaK db/conf/dawak/dawak2003.html#KriegelKG03