@article{DAN_1993_328_2_a5,
     author = {V. I. Ryazanov},
     title = {Convergence of characteristics, the {Fourier} transformation, and},
     journal = {Doklady Akademii Nauk},
     pages = {150--152},
     publisher = {mathdoc},
     volume = {328},
     number = {2},
     year = {1993},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1993_328_2_a5/}
}