@article{chen2020wireless,
  title={Wireless powered {IoE} for {6G}: Massive access meets scalable cell-free massive {MIMO}},
  author={Chen, Shuaifei and Zhang, Jiayi and Jin, Yu and Ai, Bo},
  journal={China Communications},
  volume={17},
  number={12},
  pages={92--109},
  year={2020},
  month={Dec.},
  publisher={IEEE}
}