@article{ZNSL_1991_195_a7,
     author = {P. V. Krauklis and M. V. Soferstein and L. S. Chlav},
     title = {Experimental proof of existence $K_r$-wave in cased boreholes},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {66--68},
     publisher = {mathdoc},
     volume = {195},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1991_195_a7/}
}