@article{DAN_1994_334_2_a1,
     author = {A. V. Arutyunov and S. M. Aseev},
     title = {The maximum principle in optimal control problems with phase constraints. {Nondegeneracy} and stability},
     journal = {Doklady Akademii Nauk},
     pages = {134--137},
     publisher = {mathdoc},
     volume = {334},
     number = {2},
     year = {1994},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1994_334_2_a1/}
}