2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/100779This paper has been withdrawn by the authors, as it contains some errors. The core of it has been entirely rewritten in math.FA/0510454.This paper has ben withdrawnMathematical PhysicsQuantum Algebra81R60From Stokes' formula to cyclic Hochschild cocycles on classical symbolstext