“…Nowadays various nonlocal problems for partial differential equations are actively studied and one can find a lot of papers dealing with them; see [2,9,14,13,18] and references therein. We focus our attention on nonlocal problems with integral conditions for hyperbolic equations which have been studied in [1,3,4,6,12,9,25,17,19,23,27,28]. Systematic studies of nonlocal problems with integral conditions originated with the papers by Cannon [10] and Kamynin [16].…”