A note on the approximation of elliptic control problems with bang-bang controls

Discretization of interior point methods for state constrained elliptic optimal control problems: optimal error estimates and parameter adjustment

Hinze, Michael, (2011)

Elliptic control problems with gradient constraints—variational discrete versus piecewise constant controls

Günther, Andreas, (2011)

Third order convergent time discretization for parabolic optimal control problems with control constraints

Springer, Andreas, (2014)