“…This identi®cation procedure was used by [4] in a purely mechanical contest, and has shown its validity in the study of technical problems [9], [10]. Moreover, the results expounded in [2] clearly indicate that, when dealing with the electromechanical coupling phenomena, the most useful tool is given by the method of virtual power: we are con®dent that the identities (32) allow among the possible continuum models the determination of that one which better approximates the discrete re®ned model.…”