@article{GDZPPN002488299,
title = {Optimal Control and Relaxation of Nonlinear Elliptic Systems.},
journal = {Monatshefte f\"ur Mathematik},
volume = {114},
year = {1992},
pages = {209-244},
zbl = {0768.49003},
url = {http://dml.mathdoc.fr/item/GDZPPN002488299}
}
Papageorgiou, Nikolaos S. Optimal Control and Relaxation of Nonlinear Elliptic Systems.. Monatshefte für Mathematik, Tome 114 (1992) pp. 209-244. http://gdmltest.u-ga.fr/item/GDZPPN002488299/