@article{ZNSL_1980_99_a6,
     author = {I. A. Molotkov and S. A. Vakulenko},
     title = {Nonlinear longitudinal waves in inhomogeneous rods},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {64--73},
     publisher = {mathdoc},
     volume = {99},
     year = {1980},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1980_99_a6/}
}