Yasuhito Asano Yu Tezuka Takao Nishizeki Improvements of HITS Algorithms for Spam Links. 479-490 2007 conf/waim/2007 APWeb/WAIM http://dx.doi.org/10.1007/978-3-540-72524-4_50 db/conf/waim/waim2007.html#AsanoTN07