@article{ZNSL_1984_140_a7,
     author = {A. P. Kiselev},
     title = {Effect of inhomogeneity of the medium on the directivity of the simplest sources of elastic waves},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {77--87},
     year = {1984},
     volume = {140},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1984_140_a7/}
}