1. Chen, FD, You, MS: Permanence for an integrodifferential model of mutualism. Appl. Math. Comput. 186(1), 30-34 (2007)
2. Chen, FD, Liao, XY, Huang, ZK: The dynamic behavior of N-species cooperation system with continuous time delays and feedback controls. Appl. Math. Comput. 181, 803-815 (2006)
3. Chen, FD: Permanence of a discrete N-species cooperation system with time delays and feedback controls. Appl. Math. Comput. 186, 23-29 (2007)
4. Chen, FD: Permanence for the discrete mutualism model with time delays. Math. Comput. Model. 47, 431-435 (2008)
5. Chen, FD, Yang, JH, Chen, LJ, Xie, XD: On a mutualism model with feedback controls. Appl. Math. Comput. 214, 581-587 (2009)