Sharp Dirac's theorem for DP-critical graphs

@article{Bernshteyn2018SharpDT,
  title={Sharp Dirac's theorem for DP-critical graphs},
  author={Anton Bernshteyn and Alexandr V. Kostochka},
  journal={J. Graph Theory},
  year={2018},
  volume={88},
  pages={521-546}
}
Correspondence coloring, or DP-coloring, is a generalization of list coloring introduced recently by Dvořak and Postle. In this paper we establish a version of Dirac's theorem on the minimum number of edges in critical graphs in the framework of DP-colorings. A corollary of our main result answers a question posed by Kostochka and Stiebitz on classifying list-critical graphs that satisfy Dirac's bound with equality. 
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