@article{MZM_1988_44_2_a4,
     author = {V. F. Lazutkin},
     title = {Signature of invertible symmetric matrices},
     journal = {Matemati\v{c}eskie zametki},
     pages = {202--207},
     publisher = {mathdoc},
     volume = {44},
     number = {2},
     year = {1988},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1988_44_2_a4/}
}