%0 Journal Article %A Fiacca, Antonella %A Papageorgiou, Nikolaos S. %A Papalini, Francesca %T On the existence of optimal controls for nonlinear infinite dimensional systems %J Czechoslovak Mathematical Journal %D 1998 %P 291-312 %V 48 %N 2 %U http://geodesic.mathdoc.fr/item/CMJ_1998_48_2_a6/ %G en %F CMJ_1998_48_2_a6