We consider two systems possessing invariant and globally attracting sets A1 and A2, respectively (global attractors) and assume that each attracting set is robust with respect to external perturbations in the input-to-state
stability sense. We ask, under which conditionsan interconnection of these systems possesses the same property with respect to some setA. An important part of this question is, how the corresponding attracting set A of the
interconnection can look like. Lyapunov techniques and small-gain approach will be applied in order to answer these questions.
