“…Among different kinds of cooperative control formats, consensus control, which aims at controlling all agents to achieve the same objective, has been investigated tremendously thanks to the impressive framework-building works [2][3][4]. After that, many consensus results have been presented from undirected to directed communication topology concerning different dynamics, for instance, fractional-order [5], first-order, double integrator [6,7], second-order, general linear [8,9] and nonlinear dynamics. Particularly, Li [10] presented a unified framework by expanding conventional observers to distributed observers, which is a significant breakthrough to solve the consensus problem and synchronization of complex networks.…”