Proof of Toft's Conjecture: Every Graph Containing No Fully Odd K4 Is 3-Colorable

@inproceedings{Zang1998ProofOT,
  title={Proof of Toft's Conjecture: Every Graph Containing No Fully Odd K4 Is 3-Colorable},
  author={Wenan Zang},
  booktitle={COCOON},
  year={1998}
}
A fully odd K4 is a subdivision ofK4 such that each of the six edges of the K4 is subdivided into a path of odd length. In 1974, Toft conjectured that every graph containing no fully odd K4 can be vertex-colored with three colors. The purpose of this paper is to prove Toft’s conjecture.