Bharat K. Bhargava Yuhui Zhong Yunhua Lu 330-339 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2737&spage=330 2003 conf/dawak/2003 DaWaK db/conf/dawak/dawak2003.html#BhargavaZL03