%0 Journal Article %A J. Gresser %T The range of a planar function with ambiguous points %J Fundamenta Mathematicae %D 1969 %P 129-132 %V 65 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/fm-65-2-129-132/ %R 10.4064/fm-65-2-129-132 %G en %F 10_4064_fm_65_2_129_132