@article{CRMATH_2003__336_7_615_0,
     author = {Stuart, David M.A.},
     title = {Geodesics and the {Einstein-nonlinear} wave system},
     journal = {Comptes Rendus. Math\'ematique},
     pages = {615--618},
     publisher = {Elsevier},
     volume = {336},
     number = {7},
     year = {2003},
     doi = {10.1016/S1631-073X(03)00126-2},
     language = {en},
     url = {http://archive.numdam.org/articles/10.1016/S1631-073X(03)00126-2/}
}