%0 Journal Article %A V. A. Il'in %A A. A. Kuleshov %T Necessary and sufficient conditions for a~generalized solution to the initial-boundary value problem for the wave equation to belong to $W^1_p$ with~$p\geq1$ %J Informatics and Automation %D 2013 %P 115-120 %V 283 %I mathdoc %U http://geodesic.mathdoc.fr/item/TRSPY_2013_283_a7/ %G ru %F TRSPY_2013_283_a7