1. 3Leathern, J.G., Volume and Surface Integrals Used in Physics, Hafner Publishing Co.,New York, 1960, pp. 12-26.
2. 4Ogana, W. "Computation of Steady Two-Dimensional Transonic Flows by an Integral Equation Method," Ph.D. dissertation,1976, Stanford University, Calif.
3. 5Courant, R. and John, F., Introduction to Calculus and Analysis, Vol.2, Wiley, New York, 1973, pp.556-558.