@article{PIM_1985_N_S_38_52_a20,
     author = {Hukum Singh},
     title = {On the {Generalized} {Gauss} {Lemma} in {Lorentzian} {Manifolds}},
     journal = {Publications de l'Institut Math\'ematique},
     pages = {165 },
     publisher = {mathdoc},
     volume = {_N_S_38},
     number = {52},
     year = {1985},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PIM_1985_N_S_38_52_a20/}
}