Power spectral analysis of a beat-to-beat heart rate and blood pressure variability as a possible marker of sympatho-vagal interaction in man and conscious dog - Pagani, M; Lombardi, F; Guzzetti, S; Rimoldi, O; Furlan, R; Pizzinelli, P; Sandrone, G; Malfatto, G; Dell’Orto, S; Piccaluga, E (Circ Res, 1986)
et al.