@article{ZNSL_1979_89_a18,
     author = {M. M. Popov},
     title = {Correctness of the problem of whispering gallery waves in a~vicinity of the-points where boundary's curvature vanishes},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {261--269},
     year = {1979},
     volume = {89},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1979_89_a18/}
}