TY  - JOUR
AU  - Tutte, W. T.
TI  - Chromatic Sums for Rooted Planar Triangulations: The Cases λ = 1 and λ = 2
JO  - Canadian journal of mathematics
PY  - 1973
SP  - 426
EP  - 447
VL  - 25
IS  - 2
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CJM-1973-043-3/
DO  - 10.4153/CJM-1973-043-3
ID  - 10_4153_CJM_1973_043_3
ER  -