[1］Wu  J H, Zhao X Q，  He  X Z. Global asymptotic behavior in almost periodic Kolmogorov equations and chemostat models. Nonlin World, 1996, 3: 589-611

[2]Teng Z D,  Chen   L S. The positive periodic solutions of periodic Kolmogorove type systems with delays. Acta Mathematicae Applicatae Sinica, 1999, 22: 446-456

[3]范猛, 王克. 多种群生态竞争系统周期正解的存在性和全局吸引性. 数学学报, 2000,43(1): 77-82

[4] Lansun C.  Mathematical Models and Methods in Ecology.  Beijing：Science Press, 1988(in Chinese)

[5] de Mottoni P, Schiaffino A.  Competition system with periodic coefficient:A geometric approach.  J Math Biol, 1981, 11: 319-335

[6]Cushing J M. Two species competition in a periodic environment. J Math Biol, 1980, 10: 385-400

[7] Cushing J M.  Periodic LotkaVolterra competition equations. J Math Biol,  1986, 24: 381-403

[8]Ahmad S.  On almost periodic solutions of the competing species problems. Proc Amer Math Soc, 1988, 102: 855-865

[9]Ahmad S.  On the nonautonomous VolterraLotka competition equations. Proc  Amer Math Soc, 1993, 177: 199-204

[10]Gopalsamy K.  Global asymptotic stability in a almost periodic LotkaVolterra system. J Austral Math Soc(Ser B), 1986, 28: 346-360

[11]Gopalsamy K.  Global asymptotic stability in a  periodic LotkaVolterrasystem.  J Austral Math Soc(Ser B), 1985, 27: 66-72

[12]lvarz C, Lazer A C.  An application of topological degree to the periodic competing species problem.  J Austral Math Soc Ser B, 1986, 28: 202-21

[13] 马知恩. 种群生态学的数学建模与研究. 合肥：安徽科技出版社, 1996

[14] 文贤章. 多种群生态捕食食饵时滞系统正周期解的全局吸引性. 数学学报, 2002, 45(1): 83-92

[15]Yang P H,  Xu R.  Global attractivity of the periodic LotkaVolterra system.  J Math Anal Appl, 1999, 233: 221-232

[16]Hale J K. Asymptotic behavior of dissipative system. Math Surveys Monographs 25. Amer Math Soc, Rhode Island: Providence, 1988

[17 ]Zhao X Q.  Uniform persistence and periodic coexistence states in  infinitedimensional periodic semiflows with applications. Canadian Applied Mathematics Quarterly, 1995, 3(4): 473-495