@techreport{bethel07variable,
  author =	 {E. Wes Bethel and Luke J. Gosink and John
                  C. Anderson and Kenneth I. Joy},
  title =	 {Variable Interactions in Query-Driven Visualization},
  number =	 {LBNL-63674},
  institution =	 {Lawrence Berkeley National Laboratory},
  month =	 dec,
  year =	 2007
}