@article{DAN_1992_323_6_a10,
     author = {V. V. Filippov},
     title = {Stationary points and some geometric properties of solutions of},
     journal = {Doklady Akademii Nauk},
     pages = {1043--1047},
     publisher = {mathdoc},
     volume = {323},
     number = {6},
     year = {1992},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1992_323_6_a10/}
}