Three-coloring triangle-free graphs on surfaces IV. Bounding face sizes of 4-critical graphs

@article{Dvok2021ThreecoloringTG,
title={Three-coloring triangle-free graphs on surfaces IV. Bounding face sizes of 4-critical graphs},
author={Zdeněk Dvoř{\'a}k and Daniel Kr{\'a}l and Robin Thomas},
journal={J. Comb. Theory, Ser. B},
year={2021},
volume={150},
pages={270-304}
}
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• J. Comb. Theory, Ser. B
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