@article{DAN_1976_229_2_a2,
     author = {V. F. Dem'yanov},
     title = {On the extremal basis method},
     journal = {Doklady Akademii Nauk},
     pages = {272--275},
     publisher = {mathdoc},
     volume = {229},
     number = {2},
     year = {1976},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1976_229_2_a2/}
}