@article{<a href="http://dblp.uni-trier.de/db/about/bibtex.html">DBLP</a>:journals/pvldb/ShengZTJ12,
  author    = {Cheng Sheng and
               Nan Zhang and
               Yufei Tao and
               Xin Jin},
  title     = {Optimal Algorithms for Crawling a Hidden Database in the
               Web},
  journal   = {PVLDB},
  volume    = {5},
  number    = {11},
  year      = {2012},
  pages     = {1112-1123},
  ee        = {http://vldb.org/pvldb/vol5/p1112_chengsheng_vldb2012.pdf},
  bibsource = {DBLP, http://dblp.uni-trier.de}
}