Bifurcation analysis in a kind of fourth-order delay differential equation. Cui, Xiaoqian, Wei, Junjie (2009) Discrete Dynamics in Nature and Society
Bifurcation analysis on a delayed SIS epidemic model with stage structure. Liu, Li, Li, Xiangao, Zhuang, Kejun (2007) Electronic Journal of Differential Equations (EJDE) [electronic only]