Assessment of autonomic regulation in chronic congestive heart failure by heart rate spectral analysisJ. Philip Saul, Richard J. Cohen, Leonard S. Lilly et al.|The American Journal of Cardiology|1988Cited by 710
Modulation of cardiac autonomic activity during and immediately after exerciseYasuyuki Arai, Wilson S. Colucci, Leonard S. Lilly et al.|American Journal of Physiology-Heart and Circulatory Physiology|1989Cited by 703
Power spectrum analysis of heart rate variability in human cardiac transplant recipients.Kenneth Sands, Richard J. Cohen, F J Schoen et al.|Circulation|1989Cited by 223