1. W. Kaplan,Advanced Calculus(Addison-Wesley, Cambridge, Mass., 1953), p. 218.
2. G. Batchelor,An Introduction to Fluid Dynamics(Cambridge University Press, London, 1967), p. 71.
3. C. Truesdell,A First Course in Rational Continuum Mechanics(Academic, New York, 1977), Vol. 1, pp. 78 and 225.
4. L. Prandtl,Essentials of Fluid Dynamics(Hafner, New York, 1953), p. 32.
5. H. Lamb,Hydrodynamics(Dover, New York, 1945), p. 1.