@article{MAN_1991__291_1_164882,
     author = {Zbigniew Szafraniec},
     title = {On the number of singular ponts of a real projective hypersurface.},
     journal = {Mathematische Annalen},
     pages = {487--496},
     publisher = {mathdoc},
     volume = {291},
     number = {1},
     year = {1991},
     zbl = {0724.14002},
     url = {http://geodesic.mathdoc.fr/item/MAN_1991__291_1_164882/}
}