@unpublished{BiccariZuazua2021, author = {Biccari, U and Zuazua, E}, title = {Multilevel control by duality}, url = {https://opus4.kobv.de/opus4-trr154/431}, year = {2021}, language = {en}, type = {Preprint}, institution = {TRR 154} } @unpublished{BiccariWarmaZuazua, author = {Biccari, U and Warma, M and Zuazua, E}, title = {Control and Numerical approximation of Fractional Diffusion Equations}, url = {https://opus4.kobv.de/opus4-trr154/436}, language = {en}, type = {Preprint}, institution = {TRR 154} }