%0 Journal Article %A O. N. Shablovskii %T Wave equation with cubic nonlinearity and excitation of oscillations in the ``medium-source'' system %J Vestnik Ûžno-Uralʹskogo gosudarstvennogo universiteta. Seriâ, Matematika, mehanika, fizika %D 2021 %P 44-56 %V 13 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/VYURM_2021_13_4_a5/ %G ru %F VYURM_2021_13_4_a5