@article{DAN_1979_249_2_a1,
     author = {M. M. Vishik},
     title = {On a non-archimedean analogue of perturbation theory},
     journal = {Doklady Akademii Nauk},
     pages = {267--271},
     publisher = {mathdoc},
     volume = {249},
     number = {2},
     year = {1979},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1979_249_2_a1/}
}