Ulrich Langer, Stefan Reitzinger, Josef Schicho,
"Symbolic Methods for the Element Preconditioning Technique"
, in F. Winkler and U. Langer: Symbolic and Numerical Scientific Computation, Vol. 2630, Springer, Heidelberg, Seite(n) 293 - 308, 2003
Original Titel:
Symbolic Methods for the Element Preconditioning Technique