Monotone Circuits for Matching Require Linear Depth

@inproceedings{Raz1990MonotoneCF,
  title={Monotone Circuits for Matching Require Linear Depth},
  author={Ran Raz and Avi Wigderson},
  booktitle={STOC},
  year={1990}
}
We prove the monotone circuits computing the perfect matching function on $n$vertex graphs require $\Omega(n)$ depth. This implies an exponential gap between the depth of monotone and nonmonotone circuits.