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2. C. Bernard: Introduction à I’étude de la medecine experimentale (1866); Reedited (Editions P. Beltond, Paris 1966) p.116
3. E. Durkheim: Les formes élementaires de la vie religieuse (Alcan, Paris 1912)
4. J. Moser: Stable and Random Motions in Dynamical Systems (University Press, Princeton 1973)
5. V.I. Arnold, A. Avez: Ergodic Problems of Classical Mechanics (Benjamin, New York 1968)