@article{DAN_1991_316_1_a10,
     author = {I. I. Shamaev},
     title = {Operators of diffusion type},
     journal = {Doklady Akademii Nauk},
     pages = {47--50},
     publisher = {mathdoc},
     volume = {316},
     number = {1},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1991_316_1_a10/}
}