Derivation of reference distribution functions for Tokamak-plasmas by statistical thermodynamics Giorgio Sonnino, Alessandro Cardinali, Philippe Peeters, György Steinbrecher, Alberto Sonnino and Pasquale Nardone Eur. Phys. J. D, 68 3 (2014) 44 Published online: 11 March 2014 DOI: 10.1140/epjd/e2013-40287-x