%0 Journal Article
%A Fr. Fabricius-Bjerre
%T A relation between the numbers of singular points and singular lines of a plane closed curve.
%J Mathematica Scandinavica
%D 1977
%P 20-24
%V 40
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MS2_1977__40_166511/
%F MS2_1977__40_166511