Shang, Yilun. “Global Stability of Disease-Free Equilibria in a Two-Group SI Model With Feedback Control”. Nonlinear Analysis: Modelling and Control 20, no. 4 (October 27, 2015): 501–508. Accessed August 19, 2025. https://www.zurnalai.vu.lt/nonlinear-analysis/article/view/13508.