Stoll, Martin Numerical Linear Algebra for Dynamical Systems, Max Planck Institute for Dynamics of Complex Technical Systems, Max Planck Society;
Stoll, M., Pearson, J. W., & Wathen, A. J. (2014). Preconditioners for state-constrained optimal control problems with Moreau-Yosida penalty function. Numerical Linear Algebra with Applications, 21(1), 81-97. doi:10.1002/nla.1863.