1. K. G. Davis and L. M. Hogan. To be published.
2. H. S. Carslaw and J. C. Jaeger. Conduction of Heat in Solids. Oxford (1959), Chapter 4.
3. E. R. G. Eckert and J. F. Gross. Introduction of Heat and Mass Transfer. McGraw-Hill, p. 28 (1963).
4. Handbook of Chemistry and Physics, C.R.C., 50th Edition (1969-70), Section E2.