1. F. A. Champion, “Corrosion Testing Procedures,” 2nd Edn, 1964, Chapman and Hall, London, p 204.
2. “The Metal Analyst,” 1962, Buehler Ltd, Evanston, Illinois, p 55.
3. A. K. Graham, “Electroplating Engineering Handbook,” 1st Edn, 1955, Reinhold Publishing Corporation, New York, p 158.