@article{DAN_1984_274_1_a4,
     author = {S. P. Novikov and I. A. Taimanov},
     title = {Periodic extremals of multivalued or not everywhere positive functionals},
     journal = {Doklady Akademii Nauk},
     pages = {26--28},
     publisher = {mathdoc},
     volume = {274},
     number = {1},
     year = {1984},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1984_274_1_a4/}
}