[1] I. Bock, J. Lovíšek: 
Optimal contгol of a viscoelastic plate bending. Math. Nachr. 125 (1968), 135-151. 
MR 0847355[2] I. Bock, J. Lovíšek: 
An optimal control problem for a pseudoparabolic variational inequality. Appl. Math. 31 (1992), 1, 62-80. 
MR 1152158[3] H. Gajewski K. Gröger, K. Zacharias: 
Nichtlineare Operatorgleichungen und Operatordifferentialgleichungen. Akademie-Verlag, Berlin 1974. 
MR 0636412[4] J. Sokolowski: 
Differential stability of solutions to constrained optimal control problems. Appl. Math. Optim. 13 (1985), 97-115. 
MR 0794173[5] J. Sokolowski: 
Sensitivity analysis of control constrained optimal control problems for distributed parameter systems. SIAM J. Control Optim. 25 (1987), 1542-1556. 
MR 0912455 | 
Zbl 0647.49019