%0 Journal Article %J Frontiers in physiology %D 2015 %T Nonlinear digital signal processing in mental health: characterization of major depression using instantaneous entropy measures of heartbeat dynamics %A G. Valenza %A R. G. Garcia %A L. Citi %A E. P. Scilingo %A C. A. Tomaz %A R. Barbieri %K Bioengineering %B Frontiers in physiology %V 6 %G eng