A simple characterization of special matchings in lower Bruhat intervals

@article{Caselli2018ASC,
  title={A simple characterization of special matchings in lower Bruhat intervals},
  author={Fabrizio Caselli and Mario Marietti},
  journal={Discret. Math.},
  year={2018},
  volume={341},
  pages={851-862}
}
We give a simple characterization of special matchings in lower Bruhat intervals (that is, intervals starting from the identity element) of a Coxeter group. As a byproduct, we obtain some results on the action of special matchings. 

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