1. H. Glauert, The Elements of Aerofoil and Airscrew Theory. Cambridge: Cambridge University Press (1926) p. 87.
2. G.K. Batchelor, An Introduction to Fluid Mechanics. Cambridge: Cambridge University Press (1967) p. 467.
3. L.M. Milne-Thomson, Theoretical Aerodynamics, 2nd edn. London: MacMillan & Co. (1952) p. 138.
4. B. Thwaites (ed.), Incompressible Aerodynamics. Oxford: Clarendon Press (1960) p. 123.
5. N.E. Kochin, I.A. Kibel’ and N.V. Roze, Theoretical Hydrodynamics. New York: Interscience Publishers (1964).