Cyclic Coloring of Plane Graphs with Maximum Face Size 16 and 17
  Plummer and Toft conjectured in 1987 that the vertices of every 3-connected plane graph with maximum face size D can be colored using at most D+2 colors in such a way that no face is incident with two vertices of the same color. The conjecture has been proven for D=3, D=4 and D>=18. We prove the conjecture for D=16 and D=17. 
Zdenek Dvorak, Michael Hebdige, Filip Hlasek, Daniel Kral, Jonathan   Noel
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