@article{ZNSL_1979_89_a0,
     author = {V. M. Babich},
     title = {A~point source of oscillation in a~neighbourhood of a~concave {mirror.~II}},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {3--13},
     publisher = {mathdoc},
     volume = {89},
     year = {1979},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1979_89_a0/}
}