1. R. V. CHURCHILL, “Introduction to Complex Variables and Applications.” McGraw-Hill, New York, 1948.
2. R. V. CHURCHILL, “Modem Operational Mathematics in Engineering.” McGraw-Hill, New York, 1944.
3. H. S. CARSLAW AND J. C. JAEGER, “Conduction of Heat in Solids.” Oxford Univ. Press, London and New York, 1959.