%0 Journal Article %A Nguyen Van Chau %T Note on the Jacobian condition and the non-proper value set %J Annales Polonici Mathematici %D 2004 %P 203-210 %V 84 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/ap84-3-2/ %R 10.4064/ap84-3-2 %G en %F 10_4064_ap84_3_2