7Forbes E, Pekala R. Psychophysiological effects of several stress management techniques. Psychological Reports, 1993, 72:19 - 27.
8Eckberg DL. Human sinus arrhythmia as an index of vagal cardiac outflow. J Appl Physiol, 1983, 54:961 -966.
9Porges. Orienting in a defensive world: Mammalian modifications of our evolutionary heritage. A polyvagal theory. Psychophysiology,1995, 32:301-318.
10Hayano J,Yasuma F.Hypothesis,respiratory sinus arrhythmia is an instrinsic resting function of cardiopulmonary system [J].Cardiovasc Res,2003,58(1):1-9.