id: 05888522 dt: j an: 05888522 au: Campos, C.N.; Dantas, S.; de Mello, C.P. ti: The total-chromatic number of some families of snarks. so: Discrete Math. 311, No. 12, 984-988 (2011). py: 2011 pu: Elsevier Science B.V. (North-Holland), Amsterdam la: EN cc: ut: graph colouring; total-colouring; edge-colouring; snark ci: li: doi:10.1016/j.disc.2011.02.013 ab: Summary: The total-chromatic number $χ_T(G)$ is the least number of colours needed to colour the vertices and edges of a graph $G$ such that no incident or adjacent elements (vertices or edges) receive the same colour. It is known that the problem of determining the total-chromatic number is NP-hard, and it remains NP-hard even for cubic bipartite graphs. Snarks are simple connected bridgeless cubic graphs that are not 3-edge-colourable. In this paper, we show that the total-chromatic number is 4 for three infinite families of snarks, namely, the Flower Snarks, the Goldberg Snarks, and the Twisted Goldberg Snarks. This result reinforces the conjecture that all snarks have total-chromatic number 4. Moreover, we give recursive procedures to construct a total-colouring that uses 4 colours in each case. rv: