%0 Journal Article %A Chittaro, Francesca C. %A Stefani, Gianna %T Singular extremals in multi-input time-optimal problems: a sufficient condition %J Control and Cybernetics %D 2010 %P 1029-1068 %V 39 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/CC_2010_39_4_a6/ %G en %F CC_2010_39_4_a6