@article{FPM_2002_8_3_a13,
     author = {I. A. Rudakov},
     title = {Nonlinear vibrations of a~nonhomogeneous string},
     journal = {Fundamentalʹna\^a i prikladna\^a matematika},
     pages = {877--886},
     publisher = {mathdoc},
     volume = {8},
     number = {3},
     year = {2002},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FPM_2002_8_3_a13/}
}