@article{ZNSL_1981_117_a9,
     author = {N. Ya. Kirpichnikova},
     title = {Space-time caustic of elastic short wave field},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {147--161},
     publisher = {mathdoc},
     volume = {117},
     year = {1981},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1981_117_a9/}
}