@article{DAN_1991_317_3_a12,
     author = {Yu. D. Pletner},
     title = {Some properties of solutions of an equation of},
     journal = {Doklady Akademii Nauk},
     pages = {570--572},
     publisher = {mathdoc},
     volume = {317},
     number = {3},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1991_317_3_a12/}
}