Pair Labeelings with Given Distance

@article{Fredi1989PairLW,
  title={Pair Labeelings with Given Distance},
  author={Zolt{\'a}n F{\"u}redi and Jerrold R. Griggs and Daniel J. Kleitman},
  journal={SIAM J. Discrete Math.},
  year={1989},
  volume={2},
  pages={491-499}
}