Salh, Adeeb, et al. “Mitigated Pilot Contamination to Achieve Higher Downlink Data Rate in 5G Massive MIMO Systems”. International Journal of Integrated Engineering, vol. 12, no. 2, Feb. 2020, pp. 177-86, https://penerbit.uthm.edu.my/ojs/index.php/ijie/article/view/5703.