Deterministic chaos and the first positive Lyapunov exponent: a nonlinear analysis of the human electroencephalogram during sleep. - Jürgen Fell; Joachim Röschke; P. Beckmann (Biol. Cybern., 1993)

Surrogate data analysis of sleep electroencephalograms reveals evidence for nonlinearity. - Jürgen Fell; Joachim Röschke; Cornelius Schäffner (Biol. Cybern., 1996)

Nonlinear analysis of continuous ECG during sleep I. Reconstruction. - Jürgen Fell; K. Mann; Joachim Röschke; M. S. Gopinathan (Biol. Cybern., 2000)

Nonlinear analysis of continuous ECG during sleep II. Dynamical measures. - Jürgen Fell; K. Mann; Joachim Röschke; M. S. Gopinathan (Biol. Cybern., 2000)

Neural net classification of REM sleep based on spectral measures as compared to nonlinear measures. - Michael Grözinger; Jürgen Fell; Joachim Röschke (Biol. Cybern., 2001)