By using Coincidence Degree Theorem and constructing a Lyapunov functional, new criteria are presented for the existence and global attractivity of positive periodic solu- tions of a competitive predator-prey system with delays and stage-structure. In this paper, we provide a new technique of caculation on topologic degree by transforming an integral equations into an algebraic one. Moreover, what the delays and stage-structure and competition affect on the existence and global attractivity of positive periodic solutions is discussed. Finally, an example is cited to illustrate that the existen...
