@article{ZNSL_1994_210_a12,
     author = {P. V. Krauklis and G. Kovalle},
     title = {Geometrical spreading and~$Q$ of~$P_n$ waves},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {154--157},
     publisher = {mathdoc},
     volume = {210},
     year = {1994},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1994_210_a12/}
}