1. Normal Human Sleep: An Overview;Carskadon,2005
2. Rechtschaffen A, Kales A, G. Berger, W.C. Dement, A. Jacobson, L.C. Johnson, M. Jouvet, L.J. Monroe, I. Oswald, H.P. Roffward et al., 1968. A manual of standardized terminology, techniques and scoring systems for sleep stages on human subjects., National Institute of Health Publication No. 204 ed. Public Health Service, US Government Printing Office, Washington, D.C.
3. The AASM Manual for the Scoring of Sleep and Associated Events: Rules, Terminology and Technical Specifications;Iber,2007
4. A manual of standarized terminology: Techniques and criteria for scoring states of sleep and wakefulness in newborn infants;Anders,1971
5. A study on the development of sleep-wakefulness cycle in the human fetus;Okai;Early Hum. Dev.,1992