TY - RPRT TI - Optimal order multigrid preconditioners for the distributed control of parabolic equations with coarsening in space and time AU - Drăgănescu, Andrei AU - Hajghassem, Mona PY - 2022 DO - 10.1080/10556788.2021.2022145 UR - https://www.osti.gov/biblio/1979227 ID - 1979227 ER -