@article{IM2_1975_9_5_a5,
     author = {A. S. Solodovnikov and N. R. Kamyshanskii},
     title = {Poles of {pseudo-Riemannian} spaces},
     journal = {Izvestiya. Mathematics},
     pages = {1035--1068},
     year = {1975},
     volume = {9},
     number = {5},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1975_9_5_a5/}
}