%0 Journal Article
%A Arnold Oostra
%T Existential Graphs on nonplanar surfaces
%J Revista colombiana de matematicas
%D 2019
%P 205-219
%V 53
%N 2
%I mathdoc
%U http://geodesic.mathdoc.fr/item/RCM_2019_53_2_a6/
%F RCM_2019_53_2_a6