Realizations of Nonlinear Analytic Input-Output Maps. - F. Celle; J. P. Gauthier (Math. Syst. Theory, 1987)

Synthesis of Nonlinear Observers: A Harmonic-Analysis Approach. - F. Celle; J. P. Gauthier; D. Kazakos; Gauthier Sallet (Math. Syst. Theory, 1989)