1. See e.g. Cesari, L.: Asymptotic expansions and stability problems in ordinary differential equations. Berlin, Heidelberg, New York: Springer-Verlag 1962
2. Prigogine, I.: Etude thermodynamique des ph�nom�nes irr�versibles. Li�ge: Desoer 1947
3. Glansdorff, P., Prigogine, I.: Thermodynamic theory of structure, stability and fluctuations. London: Wiley 1971
4. Kampen, N.G. Van: Stochastic processes in physics and chemistry. Amsterdam: North-Holland 1982
5. Schl�gl, F.: Z. Phys.243, 303 (1971); Z. Phys.248, 446 (1971); Ber. Bunsenges. Phys. Chem.84, 351 (1980)