Chen Chen Cindy Xide Lin Matt Fredrikson Mihai Christodorescu Xifeng Yan Jiawei Han Mining Graph Patterns Efficiently via Randomized Summaries. 742-753 2009 2 PVLDB 1 http://www.vldb.org/pvldb/2/vldb09-80.pdf db/journals/pvldb/pvldb2.html#ChenLFCYH09