A posteriori error estimation of finite element approximations of pointwise state constrained distributed control problems. - Ronald H. W. Hoppe; Michael Kieweg (J. Num. Math., 2009)

Adaptive finite element methods for mixed control-state constrained optimal control problems for elliptic boundary value problems. - R. H. W. Hoppe; Michael Kieweg (Comput. Optim. Appl., 2010)