A nonlocal existence theorem for solutions of nonlinear hyperbolic equations in Hilbert space
English version (Springer): Ukrainian Mathematical Journal 19 (1967), no. 1, pp 98-99.
Citation Example: Pogorelenko V. A., Sobolevsky P. Ye. A nonlocal existence theorem for solutions of nonlinear hyperbolic equations in Hilbert space // Ukr. Mat. Zh. - 1967. - 19, № 1. - pp. 113–115.
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