%0 Journal Article
%A V. V. Matyushkov
%T The vertex function of directed graphs
%J Doklady Akademii Nauk
%D 1962
%P 37-40
%V 146
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1962_146_1_a9/
%G ru
%F DAN_1962_146_1_a9