L∞ - and l∞ - stability of interconnected systems

Sufficient conditions for the L<sub>∞</sub> - and l<sub>∞</sub> - boundedness of nonlinear interconnected systems are established. Systems which may be viewed as an interconnection of single-loop feedback systems are considered. Overall boundedness conditions are phrased iu terms of the margins by which each subsystem satisfies a certain boundedness condition. The existence of similar results for the L<sub>∞</sub> - and l<sub>∞</sub> - continuity of nonlinear interconnected systems is noted.