@article{ZNSL_1970_17_a10,
     author = {N. V. Zepelev},
     title = {Shadow zone of the boundary inhomogeneous half-space},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {209--217},
     publisher = {mathdoc},
     volume = {17},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1970_17_a10/}
}