Preprint Article Version 1 This version is not peer-reviewed Version 1 : Received: 14 July 2024 / Approved: 15 July 2024 / Online: 16 July 2024 (05:16:10 CEST) Bhuyan, M.; Sarma, K. K.; Misra, D. D.; Guha, K.; Iannacci, J. Adaptive Hybrid Beamforming Codebook Design using Multi-Agent Reinforcement Learning for Multiuser MIMO Systems. Preprints 2024, 2024071166. https://doi.org/10.20944/preprints202407.1166.v1 Bhuyan, M.; Sarma, K. K.; Misra, D. D.; Guha, K.; Iannacci, J.