F. Rezazadeh, L. Zanzi, F. Devoti, H. Chergui, X. Costa-Pérez and C. Verikoukis, "On the Specialization of FDRL Agents for Scalable and Distributed 6G RAN Slicing Orchestration," in IEEE Transactions on Vehicular Technology, vol. 72, no. 3, pp. 3473-3487, March 2023, doi: 10.1109/TVT.2022.3218158.