\bibitem{Brug84}       G.J.Brug, A.L.G.Van Den Eeden, M.Sluyters-Rehbach, J.H.Sluyters   \hskip 2mm
                       {\it The Analysis of Electrode Impedance Complicated by the Presence of a Constant Phase Element},
                       J.Electroanal.Chem. {\bf 176}, 275-295, 1984.