Sérgio Lifschitz Alberto H. F. Laender Report on the 19<sup>th</sup> Brazilian symposium on databases (SBBD 2004). 61-62 2005 34 SIGMOD Record 1 http://doi.acm.org/10.1145/1058150.1058164 db/journals/sigmod/sigmod34.html#LifschitzL05