Junhu Wang Kewen Wang Jiuyong Li Finding Irredundant Contained Rewritings of Tree Pattern Queries Using Views. 113-125 2009 APWeb/WAIM http://dx.doi.org/10.1007/978-3-642-00672-2_12 conf/waim/2009 db/conf/waim/waim2009.html#WangWL09