“…In the past few decades, synchronization problems for multiagent systems have received substantial attention, where the objective is to achieve asymptotic agreement on a common state ( state synchronization ) or output trajectory ( output synchronization ) among agents of the network through decentralized control protocols. Some early results can be found in, e.g., [4,9,11,15] , for state synchronization problems of homogeneous networks (i.e. agents are identical), and in, e.g., [1,3,18,20,21] , for output synchronization problems for heterogeneous networks.…”