@article{ZNSL_1981_104_a19,
     author = {A. S. Starkov},
     title = {Degeneration and resonance phenomena in the wave propagation problems},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {217--227},
     publisher = {mathdoc},
     volume = {104},
     year = {1981},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1981_104_a19/}
}