@article{ZNSL_1975_51_a4,
     author = {N. S. Grigor'ev},
     title = {An estimate of a~wave field in a~shadow zone in the case of diffraction of spherical wave by infinitely smooth surface},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {93--118},
     publisher = {mathdoc},
     volume = {51},
     year = {1975},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1975_51_a4/}
}