Sungchae Lim Joonseon Ahn A Hierarchical Cache Scheme for the Large-scale Web Search Engine. 925-930 2008 SNPD http://doi.ieeecomputersociety.org/10.1109/SNPD.2008.107 conf/snpd/2008 db/conf/snpd/snpd2008.html#LimA08