1. Ahmed Kerbal S., N. U.: Optimal control of nonlinear second order evolution equations. J. Appl. Math. Stoch. Anal., 6, 123–136 (1993)
2. Bian W.: Existence results for second order nonlinear evolution inclusions. Indian J. Pure Appl. Math., 11, 1177–1193 (1998)
3. Gasinski, L. Smolka, M.: An existence theorem for wave–type hyperbolic hemivariational inequalities. Math. Nachr., 242, 79–90 (2002)
4. Kartsatos, A. Markov, L.: An L 2–approach to second order nonlinear functional evolutions involving maccretive operators in Banach spaces. Diff. Integral Equations, 14, 833–866 (2001)
5. Migorski, S.: Existence, variational and optimal control problems for nonlinear second order evolution inclusions. Dynam. Syst. and Appl., 4, 513–528 (1995)