@article{ZNSL_1972_25_a11,
     author = {Z. A. Yanson},
     title = {High order approximations of asymptotic solutions for wave equation in a~plane waveguide},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {176--191},
     publisher = {mathdoc},
     volume = {25},
     year = {1972},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1972_25_a11/}
}