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2. N. Minorsky,Nonlinear Oscillations (Van Nostrand, New York, 1962).
3. W. Ebeling,Strukturbildung bei irreversiblen Prozessen (Teubner Verlag, Leipzig, 1976).
4. G. Nicolis and I. Prigogine,Self-Organization in Nonequilibrium Systems (Wiley, New York, 1977).
5. H. Haken,Synergetics, An Introduction (Springer-Verlag, Berlin, 1977);Advanced Synergetics (Springer-Verlag, Berlin, 1983).