@article{DAN_1992_323_2_a2,
     author = {S. A. Vavilov},
     title = {Geometric methods for investigating the solvability of a class of},
     journal = {Doklady Akademii Nauk},
     pages = {206--210},
     publisher = {mathdoc},
     volume = {323},
     number = {2},
     year = {1992},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1992_323_2_a2/}
}