1. Nemytskii, V.V., Stepanov, V.V.: Dover Books on Mathematics. Dover Publications, New York (1989)
2. Afraimovich, V.: Chaos 7(1), 12 (1997)
3. Afraimovich, V., Zaslavsky, G.: Phys. Rev. E 55, 5418 (1997)
4. Afraimovich, V., Ugalde, E., Urias, J.: Fractal Dimension for Poincaré Recurrences. Elsevier, Amsterdam (2006)
5. Kac, M.: Bull. Am. Math. Soc. 53(10), 1002 (1947)