1. U.R. Evans, The Corrosion of Metals, Arnold, London, 1926, p. 93.
2. H.H. Uhlig (Ed.), The Corrosion Handbook, Wiley, New York, 1948, pp. 549–551.
3. F. Tödt (Ed.), Korrosion und Korrosionsschutz, De Gruyter, Berlin, 1955, pp. 115–117.
4. W. Wiederholt, H. Kaesche (Eds.), Kathodischen Korrosionsschutz, Korrosion II, Verlag Chemie, Weinheim, 1959, p. 11.
5. U.R. Evans, An Introduction to Metallic Corrosion, Edward Arnold, London, 2nd ed., 1963, p. 30.