%0 Journal Article %A S. Walcher %T Multi-Parameter Symmetries of First Order Ordinary Differential Equations %J Journal of Lie theory %D 1999 %P 249-269 %V 9 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/JLT_1999_9_1_a10/ %F JLT_1999_9_1_a10