1. Maxwell, J. C., “A Treatise on Electricity and Magnetism”, 3rd edit. (Oxford Univ. Press, London, 1892).
2. Fricke, H., Phys. Rev., 24, 575 (1924).
3. Höber, R., “Physical Chemistry of Cells and Tissues” (Blakiston, Philadelphia, 1945).
4. Fricke, H., and Morse, St., J. Gen. Physiol., 9, 153 (1926).
5. Fricke, H., and Curtis, H. J., Nature, 133, 651 (1934).