@article{CRMATH_2009__347_15-16_971_0,
     author = {Yvonne Choquet-Bruhat and Piotr T. Chru\'sciel and Jos\'e M. Mart{\'\i}n-Garc{\'\i}a},
     title = {A property of light-cones in {Einstein's} gravity},
     journal = {Comptes Rendus. Math\'ematique},
     pages = {971--977},
     publisher = {Elsevier},
     volume = {347},
     number = {15-16},
     year = {2009},
     doi = {10.1016/j.crma.2009.06.001},
     language = {en},
}