@article{DAN_1979_249_3_a1,
     author = {V. A. Ginzburg},
     title = {The method of orbits and perturbation theory},
     journal = {Doklady Akademii Nauk},
     pages = {525--528},
     publisher = {mathdoc},
     volume = {249},
     number = {3},
     year = {1979},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1979_249_3_a1/}
}