@article{FPM_2014_19_5_a2,
     author = {A. V. Dmitruk and N. P. Osmolovskii},
     title = {On the proof of {Pontryagin's} maximum principle by means of needle variations},
     journal = {Fundamentalʹna\^a i prikladna\^a matematika},
     pages = {49--73},
     publisher = {mathdoc},
     volume = {19},
     number = {5},
     year = {2014},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FPM_2014_19_5_a2/}
}