%0 Journal Article
%A Tutte, W. T.
%T Chromatic Sums for Rooted Planar Triangulations, III: The Case λ = 3
%J Canadian journal of mathematics
%D 1973
%P 780-790
%V 25
%N 4
%U http://geodesic.mathdoc.fr/articles/10.4153/CJM-1973-080-7/
%R 10.4153/CJM-1973-080-7
%F 10_4153_CJM_1973_080_7