@article{ZNSL_1970_17_a11,
     author = {Z. A. Yanson},
     title = {High-frequency asymptotic of the solution of the wave equation in the flat-plane wavequide formed by two caustics},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {218--243},
     publisher = {mathdoc},
     volume = {17},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1970_17_a11/}
}