@article{IM2_2017_81_5_a2,
     author = {M. I. Zelikin},
     title = {An analogue of {Pontryagin's} maximum principle in problems of minimization of multiple integrals},
     journal = {Izvestiya. Mathematics },
     pages = {973--984},
     publisher = {mathdoc},
     volume = {81},
     number = {5},
     year = {2017},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_2017_81_5_a2/}
}