@article{VSPUI_2013_1_a1,
     author = {D. M. Lebedev and L. N. Polyakova},
     title = {The problem of projecting the origin on a quadric},
     journal = {Vestnik Sankt-Peterburgskogo universiteta. Prikladna\^a matematika, informatika, processy upravleni\^a},
     pages = {11--17},
     publisher = {mathdoc},
     number = {1},
     year = {2013},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VSPUI_2013_1_a1/}
}