Covering contractible edges in 3-connected graphs. II. Characterizing those with covers of size three

@article{Hemminger1993CoveringCE,
  title={Covering contractible edges in 3-connected graphs. II. Characterizing those with covers of size three},
  author={Robert L. Hemminger and Xingxing Yu},
  journal={Journal of Graph Theory},
  year={1993},
  volume={17},
  pages={247-252}
}