@article{RSM_1999__57_3_126553,
     author = {Ben-Naoum, Abdou Kouider},
     title = {The role of the {Lagrange} constant in some nonlinear waves equations.},
     journal = {Rendiconti del seminario matematico},
     pages = {175--184},
     publisher = {mathdoc},
     volume = {57},
     number = {3},
     year = {1999},
     zbl = {1098.35549},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RSM_1999__57_3_126553/}
}