1. Alexander, S.S.: The accelerator as a generator of steady growth, Quart. J. Economics 63 (1949), 174–197.
2. Alexander, S.S.: Mr. Harrod’s dynamic model, Economic J. 60 (1950), 724–739.
3. Baumol, W.J.: Economic Dynamics, 3rd edn., Macmillan, London, 1970.
4. Burmeister, E. and Dobell, A.R.: Mathematical Theories of Economic Growth, Macmillan, London, 1970.
5. Coddington, E.A. and Levinson, N.: Theory of Ordinary Differential Equation, McGraw-Hill, New York, 1955.