1. J. C. Panetta, ‘‘A mathematical model of periodically pulsed chemotherapy: Tumor recurrence and metastasis in a competition environment,’’ Bull. Math. Biol. 58, 425–447 (1996).
2. A. Lakmeche and O. Arino, ‘‘Bifurcation of nontrivial periodic solutions of impulsive differential equations arising from chemotherapeutic treatment,’’ Dyn. Control Discrete Impl. Syst. 7, 265–288 (2000).
3. A. Lakmeche and O. Arino, ‘‘Nonlinear mathematical model of pulsed-therapy of heterogeneous tumors,’’ Nonlin. Anal. Real World Appl. 2, 455–465 (2001).
4. G. Jiang and Q. Yang, ‘‘Bifurcation analysis in an SIR epidemic model with birth pulse and pulse vaccination,’’ Appl. Math. Comput. 215, 1035–1046 (2009).
5. A. Boudermine, M. Helal, and A. Lakmeche, ‘‘Bifurcation of nontrivial periodic solutions for pulsed chemotherapy model,’’ Math. Sci. Appl. E-Notes 2 (2), 22–44 (2014).