@article{AIHPA_1975__23_3_297_0,
     author = {Ihrig, E. and Sen, D. K.},
     title = {Uniqueness of timelike killing vector fields},
     journal = {Annales de l'institut Henri Poincar\'e. Section A, Physique Th\'eorique},
     pages = {297--301},
     publisher = {Gauthier-Villars},
     volume = {23},
     number = {3},
     year = {1975},
     mrnumber = {389131},
     zbl = {0316.53047},
     language = {en},
     url = {http://www.numdam.org/item/AIHPA_1975__23_3_297_0/}
}