Nonlinear Indices of Heart Rate Variability in Chronic Heart Failure Patients: Redundancy and Comparative Clinical Value - Maestri, R; Pinna, GD; Accardo, A; Allegrini, P; Balocchi, R; D’Addio, G; Ferrario, M; Menicucci, D; Porta, A; Sassi, R; Signorini, MG; La Rovere, MT; Cerutti, S (J Cardiovasc Electrophysiol, 2007)