TY  - JOUR
AU  - Tutte, W. T.
TI  - Combinatorial Oriented Maps
JO  - Canadian journal of mathematics
PY  - 1979
SP  - 986
EP  - 1004
VL  - 31
IS  - 5
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CJM-1979-091-3/
DO  - 10.4153/CJM-1979-091-3
ID  - 10_4153_CJM_1979_091_3
ER  -