@article{DAN_1990_312_4_a2,
     author = {S. A. Vavilov},
     title = {A solvability criterion for a resonance periodic problem in the},
     journal = {Doklady Akademii Nauk},
     pages = {787--790},
     publisher = {mathdoc},
     volume = {312},
     number = {4},
     year = {1990},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1990_312_4_a2/}
}