%0 Journal Article %A V. Yu. Ovsienko %A C. Roger %T Deformations of Poisson brackets and extensions of Lie algebras of contact vector fields %J Trudy Matematicheskogo Instituta imeni V.A. Steklova %D 1992 %P 135-191 %V 47 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/RM_1992_47_6_a2/ %G en %F RM_1992_47_6_a2