Dias, Joao Paulo, y Mario Figueira. 1996. «A remark on the blow-up of the solutions of the equation ut+f(u)a(u)ux=h(x,u)». Revista Matemática Complutense 9, nº 2:: 385. https://doi.org/10.5209/rev_REMA.1996.v9.n2.17588