%0 Journal Article %A Faruk Güngör %T On the Virasoro Structure of Symmetry Algebras of Nonlinear Partial Differential Equations %J Symmetry, integrability and geometry: methods and applications %D 2006 %V 2 %U http://geodesic.mathdoc.fr/item/SIGMA_2006_2_a13/ %G en %F SIGMA_2006_2_a13