1. Gender- and age-related differences in heart rate dynamics: Are women more complex than men?
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3. U. Rajendra Acharya , Jasjit S. Suri , Jos A. E. Spaan , and Shankar M . Krishnan . 2007 . Advances in Cardiac Signal Processing. Springer-Verlag Berlin Heidelberg . https://doi.org/10.1007/978-3-540-36675-1 U. Rajendra Acharya, Jasjit S. Suri, Jos A. E. Spaan, and Shankar M. Krishnan. 2007. Advances in Cardiac Signal Processing. Springer-Verlag Berlin Heidelberg. https://doi.org/10.1007/978-3-540-36675-1
4. Approximate entropy as a measure of system complexity.
5. Physiological time-series analysis: what does regularity quantify?