We present the derivation of Lyapunov and free energy functionals for gener
alized Fokker-Planck equations including those proposed by Desai and Zwanzi
g, Kuramoto, Kaniadakis and Quarati, and Plastino and Plastino. Thus, we de
monstrate a common feature of processes described by generalized Fokker-Pla
nck equations: the decrease of an appropriately defined free energy. (C) 20
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