Blockchain-Based Lightweight Multifactor Authentication for Cell-Free in Ultra-Dense 6G-Based (6-CMAS) Cellular Network. - Adnan Shahid Khan; Mohd Izzat Bin Yahya; Kartinah bt Hj Zen; Johari Abdullah; Rozeha Binti A. Rashid; Yasir Javed; Nayeem Khan; Ahmed M. Mostafa (IEEE Access, 2023)