Shingo Otsuka Masashi Toyoda Jun Hirai Masaru Kitsuregawa Extracting User Behavior by Web Communities Technology on Global Web Logs. 957-988 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3180&spage=957 2004 conf/dexa/2004 DEXA db/conf/dexa/dexa2004.html#OtsukaTHK04