Yufei Tao Ke Yi Cheng Sheng Jian Pei Feifei Li Logging every footstep: quantile summaries for the entire history. 639-650 2010 SIGMOD Conference http://doi.acm.org/10.1145/1807167.1807237 conf/sigmod/2010 db/conf/sigmod/sigmod2010.html#TaoYSPL10