F. Caetano, «On the existence of weak solutions to the Cauchy problem for a class of quasilinear hyperbolic equations with a source term»., Rev. mat. complut., vol. 17, n.º 1, pp. 147–167, jun. 2004, doi: https://doi.org/10.5209/rev_REMA.2004.v17.n1.16794