@article{SchielaGuenther2011, author = {Anton Schiela and Andreas G{\"u}nther}, title = {An Interior Point Algorithm with Inexact Step Computation in Function Space for State Constrained Optimal Control}, journal = {Numer. Math.}, volume = {119}, number = {2}, pages = {373 -- 407}, doi = {10.1007/s00211-011-0381-4}, year = {2011}, }