@article{
  author = {A. Zappone and B. Matthiesen and E.A. Jorswieck},
  year = {2017},
  month = {Feb},
  title = {Energy Efficiency in MIMO Underlay and Overlay Device-to-Device Communications and Cognitive Radio Systems},
  volume = {65},
  number = {4},
  pages = {1026-1041},
  URL = {https://doi.org/10.1109/TSP.2016.2626249},
  journal={IEEE Transactions on Signal Processing}
}