%0 Journal Article %A Kejun Zhuang %D 2010 %J International Journal of Mathematical and Computational Sciences %B World Academy of Science, Engineering and Technology %I Open Science Index 43, 2010 %T Periodicity for a Semi–Ratio–Dependent Predator–Prey System with Delays on Time Scales %U https://publications.waset.org/pdf/9158 %V 43 %X In this paper, the semi–ratio–dependent predator-prey system with nonmonotonic functional response on time scales is investigated. By using the coincidence degree theory, sufficient conditions for existence of periodic solutions are obtained. %P 780 - 783