Rajasekar Krishnamurthy Raghav Kaushik Jeffrey F. Naughton Unraveling the Duplicate-Elimination Problem in XML-to-SQL Query Translation. 49-54 2004 conf/webdb/2004 WebDB db/conf/webdb/webdb2004.html#KrishnamurthyKN04 http://webdb2004.cs.columbia.edu/papers/4-2.pdf