Gleb Skobeltsyn Flavio Junqueira Vassilis Plachouras Ricardo A. Baeza-Yates ResIn: a combination of results caching and index pruning for high-performance web search engines. 131-138 2008 SIGIR http://doi.acm.org/10.1145/1390334.1390359 conf/sigir/2008 db/conf/sigir/sigir2008.html#SkobeltsynJPB08