@article{DAN_1981_261_3_a1,
     author = {A. V. Arutyunov and N. T. Tynyanskii},
     title = {On second-order conditions in a time-optimal problem},
     journal = {Doklady Akademii Nauk},
     pages = {523--526},
     publisher = {mathdoc},
     volume = {261},
     number = {3},
     year = {1981},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1981_261_3_a1/}
}