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Existence of positive periodic solution of mutualism system with several delays. (English) Zbl 1156.34350
The authors study a mutualism system with several delays, which can be bounded and unbounded. By applying the continuation method of coincidence degree, they establish some sufficient conditions on the existence of positive periodic solutions. The results generalize and improve some existing ones.
MSC:
34K60Qualitative investigation and simulation of models
34K13Periodic solutions of functional differential equations
92D25Population dynamics (general)
47N20Applications of operator theory to differential and integral equations