@ARTICLE{9037331,
  author={Cao, Hui and Liu, Qi},
  journal={IEEE Communications Letters}, 
  title={Fast Rank-Revealing QR Factorization for Two-Dimensional Frequency Estimation}, 
  year={2020},
  volume={24},
  number={6},
  pages={1240-1243},
  doi={10.1109/LCOMM.2020.2981027}}