P. Bohannon, W. Fan, M. Flaster, and R. Rastogi. SIGMOD '05: Proceedings of the 2005 ACM SIGMOD international conference on Management of data, page 143--154. New York, NY, USA, ACM, (2005)
R. Kaushik, P. Bohannon, J. Naughton, and P. Shenoy. Proceedings of the 28th international conference on Very Large Data Bases, page 239--250. VLDB Endowment, (2002)