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Positive periodic solutions of a discrete mutualism model with time delays. (English) Zbl 1081.92042
Summary: A discrete periodic mutualism model with time delays is investigated. By using R. E. Gaines and J. L. Mawhin’s continuation theorem of coincidence degree theory [Coincidence degree, and nonlinear differential equations. (1977; Zbl 0339.47031)], the existence of positive periodic solutions of the model is established.

MSC:
92D40Ecology
34K13Periodic solutions of functional differential equations
34K60Qualitative investigation and simulation of models