“…Since weak solutions of hyperbolic equations are likely to be discontinuous, their product with Dirac measures is unstable and the relevant theory is developed in [5,9,12,24,32,36]. At the numerical level, the key point is to be able to compute accurately such measure-valued terms: some attempts have already been proposed in [17,19,20,22,23]; see also [8,21,40,39] for closely related works. We stress that our results do not contradict [26].…”