Assuming price-sensitive stochastic demands and effort-sensitive stochastic returns,a multi-echelon closed-loop supply chain with 3PRLP is established.A target rebate-punish contract between the manufacturer and the 3PRLP is designed.The closed-form analytic expressions for both united optimization strategies in cen- tralized closed-loop system and the one-leader-multiple-follower Stackelberg strategies in decentralized system are deduced,and comparisons are made from the viewpoint of contract c...