1. Abramowitz M. and Stegun I. A. (1972). Handbook of Mathematical Functions National Bureau of Standards Washington D.C.
2. Benjamin J. R. and Cornell C. A. (1970). Probability Statistics and Decision for Civil Engineers McGraw‐Hill Book Co. Inc. New York N.Y.
3. Carslaw H. S. and Jaeger J. C. (1973). Conduction of Heat in Solids Oxford New York N.Y.