@article{ZNSL_1979_89_a14,
     author = {I. A. Molotkov and A. B. Plachenov},
     title = {Ungtationary modes in a~thin and curved waveguide of variable width},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {210--218},
     year = {1979},
     volume = {89},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1979_89_a14/}
}