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Periodic solutions of a class of nonautonomous discrete time semi-ratio-dependent predator-prey systems. (English) Zbl 1100.92064
Summary: We establish sufficient criteria for the existence of positive periodic solutions for a class of discrete time semi-ratio-dependent predator-prey interaction models based on systems of nonautonomous difference equations. The approach involves the coincidence degree and its related continuation theorem as well as some prior estimates.
MSC:
92D40Ecology
39A11Stability of difference equations (MSC2000)