1. C. Zener,Thermoelectricity, edited by P. H. Egli (John Wiley & Sons, Inc., New York, 1960), p. 8.
2. See, e.g., A. H. Wilson,The Theory of Metals(Cambridge University Press, New York, 1953), 2nd ed., p. 232.
3. A good discussion of ohmic contacts is given by L. V. Azaroff,Introduction to Solids(McGraw-Hill Book Company, Inc., New York, 1960), p. 343.