A plane graph G is edge-face k-colorable if the elements of E(G)∪ F(G) can be colored with k colors so that any two adjacent or incident elements receive different colors. Sanders and Zhao conjectured that every plane graph with maximum degree △ is edge-face (△+2)-colorable and left the cases △ ∈ {4, 5, 6} unsolved. In this paper, we settle the case △ = 6. More precisely, we prove that every plane graph with maximum degree 6 is edge-face 8-colorable.
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