@article{DAN_1977_235_1_a3,
     author = {A. S. Leonov},
     title = {Calculation of the values of unbounded operators by the averaging method},
     journal = {Doklady Akademii Nauk},
     pages = {23--26},
     publisher = {mathdoc},
     volume = {235},
     number = {1},
     year = {1977},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1977_235_1_a3/}
}