@techreport{NonegativeCharacteristicForm,
  title = "{hp-Version Discontinuous} Galerkin Methods with Interior Penalty for Partial Differential Equations with Nonnegative Characteristic
Form",
  author = "K. Harriman and P. Houston and W. Senior and E. S\"uli",
  year = "2002",
  institution = "Oxford University Computing Laboratory",
  number = "NA02/21",
}